Plating apparatus, plating method, and method for manufacturing semiconductor device

ABSTRACT

A plating apparatus according to the present invention is provided with a plating tank  100  in which an anode electrode  5  is provided, the plating apparatus performing the plating by (i) streaming a plating solution and an electrolytic liquid into the plating tank  100,  (ii) emitting a jet of the plating solution to the plating-target face W of the semiconductor wafer  1  from the underneath of the semiconductor wafer  1,  and (iii) streaming the electrolytic liquid to the anode electrode  5  while electrically conducting between the semiconductor wafer  1  and the anode electrode  5,  the plating tank including a partition in between the semiconductor wafer  1  and the anode electrode  5,  and the partition (i) separating the semiconductor wafer  1  and the anode electrode  5  and (ii) dividing the plating tank  100  into a plating-target substrate room and an anode electrode room. Thus, in a face-down type fountain plating apparatus, the plating quality would not be degraded by micro foreign solid particles originated from, for example, a black film while maintaining the operability of the apparatus.

This Nonprovisional application claims priority under 35 U.S.C. §119(a)on Patent Applications (i) No. 112888/2005 filed in Japan on Apr. 8,2005 and (ii) No. 202283/2005 filed in Japan on Jul. 11, 2005, theentire contents of which are hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to (i) a plating apparatus, (ii) a platingmethod, and (iii) a method for manufacturing a semiconductor device, allof which are excellent for finely plating a plating-target face of, forexample, a semiconductor wafer in order to form wiring.

BACKGROUND OF THE INVENTION

In the recent years, metal plating has been utilized for forming awiring on, for example, a semiconductor wafer. Known conventionalapparatuses utilized for metal plating include a face-down type fountainplating apparatus, a rack-method vertical plating apparatus, and aface-up type fountain plating apparatus.

The face-down type fountain plating apparatus, as illustrated in FIG.11, is provided with: a wafer holder 2′ that holds a semiconductor wafer1′; a cup 3′; a plating solution jet tube 4′ for supplying platingsolution to the cup 3′; and an anode electrode 5′. The anode electrode5′ is normally made of copper mixed with phosphorus. The anode electrode5′ is provided in the cup 3′. The wafer holder 2′ is provided to the cup3′. The semiconductor wafer 1′ is held on top of the cup 3′ by the waferholder 2′. In the face-down type fountain plating apparatus, the platingsolution jet tube 4′ is disposed underneath of the semiconductor wafer1′. With this structure, jets of plating solution emitted from theplating solution jet tube 4′ is applied on the semiconductor wafer 1′from the underneath so as to plate the plating-target face (face to beplated).

The face-down type fountain plating apparatus is provided with thefollowing components, although these components are not illustrated inFIG. 11: a plating solution tank disposed in such a way as to surroundthe cup 3′; a plating solution storage tank that functions as a supplysource of plating solution; a pump utilized for circulating the platingsolution within the plating apparatus; a filter that filters off foreignsolid particles contained in the plating solution; and a pipe thatconnects the above components.

With the face-down type fountain plating apparatus, the pump conveys theplating solution from the plating solution storage tank to the bottom ofthe cup 3′ via the filter. Then, the plating solution streams into thecup 3′ from the underneath of the cup 3′ through the plating solutionjet tube 4′, passes by the anode electrode 5′, and finally reaches theplating-target face of the semiconductor wafer 1. Subsequently, theplating solution is drained out of the cup 3′ from an upper edge of thecup 3′ (the plating solution is drained through a gap between the waferholder 2′ and the cup 3′). Finally, the plating solution is collected bythe plating solution tank and returned to the plating solution storagetank.

In the face-down type fountain plating apparatus is provided an “outletopening through which the plating solution streamed into the platingtank is partially drained out of the plating tank from (i) a throughhole made through the anode electrode or (ii) a vicinity of the anodeelectrode.” Another known plating apparatus is that adopting an inertelectrode, a typical example of which includes platinum, as an anodeelectrode.

The rack-method vertical plating apparatus, as illustrated in FIG. 12,is provided with an anode electrode 6″, a rack 24, and a plating tank12. The anode electrode 6″ is normally disposed in an anode bag 13 madeof cloth having a raised back. As the anode electrode 6″, (i) aball-shaped copper mixed with phosphorus that is placed in a bascketmade of titanium or (ii) a copper plate made of copper mixed withphosphorus is used. The rack 24 is a plate-shaped jig provided with apower source for supplying the semiconductor wafer 1 with power. Throughthe jig is made a hole having an inner diameter slightly smaller thanthat of the semiconductor wafer 1. Finally, the plating tank 12 isprovided with a wafer holder 25 and a squeegee (not illustrated). Thewafer holder 25 stabilizes the semiconductor wafer 1 on the rack 24, andinsulates the rear face of the semiconductor wafer 1. The squeegeeagitates the plating solution.

The rack-method vertical plating apparatus is provided with thefollowing components, although these components are not illustrated inFIG. 12: a plating solution tank; a plating solution storage tank thatfunctions as a supply source of the plating solution; a pump utilizedfor circulating the plating solution within the plating apparatus; afilter that filters off foreign solid particles contained in the platingsolution; a pipe that connects the above components; and accessoryunits.

The pump conveys the plating solution from the storage tank to an inletopening 14 via the filter. Then, the plating solution streams in thevicinity of the anode bag 13, which covers the anode electrode 6, in theplating tank 12. Subsequently, the plating solution reaches theplating-target face of the semiconductor wafer 1. Then, the platingsolution is drained out from the upper edge of the plating tank 12, andstreams into the dam 15. Finally, the plating solution is returned tothe plating solution storage tank via the return tube that constitutes apart of the dam 15. Such rack-method vertical plating apparatus isdisclosed in Document 1: Janapese Unexamined Patent Publication2000-87299 (published on Mar. 28, 2000).

Further, in the face-up type fountain plating apparatus, theplating-target face of a semiconductor wafer faces upward, and an anodeelectrode is so disposed as to face the plating-target face. Therefore,the plating solution is supplied onto the upper face of thesemiconductor wafer. Such face-up type fountain plating apparatus isdisclosed in, for example, Document 2: Japanese Unexamined PatentPublication No. 2001-49498 (published on Feb. 20, 2001) or Document 3:Japanese Unexamined Patent Publication no. 2001-24303 (published on Jan.26, 2001).

The face-down type fountain plating apparatus has a problem in thatmicro foreign solid particles adhere to the plating-target face, andtherefore the plating quality is degraded. This problem is originatedfrom the surface of the anode electrode in the path through which theplating solution streams; the plating solution supplied from the platingsolution storage tank by the pump is filtrated by the filter, issupplied to the cup from the underneath thereof, passes by the vicinityof the anode electrode, and reaches the plating-target face of thesemiconductor wafer. If the anode electrode includes copper mixed withphosphorus then a film in black called black film is formed on thesurface of the anode electrode. The black film is made of copper complex(Cu⁺) with one valence electron, which copper complex contains chlorine(Cl) or phosphorus (P). The black film is formed by a chemicalcombination with copper ion having one valence electron, which copperion is dissolved from the anode electrode.

The black film suppresses a disproportionation reaction of copperaccording to formula (1) below, thereby preventing generation of slime.2Cu⁺→Cu+Cu²⁺  (1)

However, the black film formed on the surface of the anode electrode iseasily peeled off therefrom. A small piece of peeled black film isconveyed, along with a stream of the plating solution, to theplating-target face of the semiconductor wafer. This causes a problem inthat the black film adheres to a plating-target face of thesemiconductor wafer.

Such problem caused by the black film can be prevented by adopting aninert electrode as the anode electrode. In this case, however, anadditive agent contained in the plating solution is oxidativelydecomposed on the surface of the anode electrode. This causes a problemin that the consumption of the plating solution increases. Anotherproblem is that the oxidative decomposition may generate a decompositionproduct, and the decomposition product would contaminate the platingsolution.

In contrast, with the conventional rack-method vertical platingapparatus, the anode electrode containing copper mixed with phosphorusis disposed in the anode bag made of cloth having raised back. Thisprevents the foreign solid particles, which are generated from the blackfilm, from adhering to the semiconductor wafer. However, in order tohold the semiconductor wafer in the plating tank, the vertical platingapparatus requires fixedly holding the semiconductor wafer on the rack.This causes problems in that (i) the operability is degraded, (ii) theplating quality is degraded, and (iii) automation of operation is madedifficult.

Further, in the face-up type fountain plating apparatus according toDocument 2, the bottom portion of the anode room includes an ionexchange resin or a porous neutral membrane to prevent the black filmfrom peeling, which may be caused by dryness, and the anode room isfilled with the plating solution. Further, in the face-up type fountainplating apparatus according to Document 3, the bottom face of the anoderoom includes a porous element having numerous thin holes.

Further, an apparatus having a different structure from the aboveplating apparatuses is disclosed in Document 4: Japanese UnexaminedPatent Publication No. 2003-73889 (published on Mar. 12, 2003). Document4 teaches a copper-plating apparatus that electrically plates asemiconductor wafer with copper, the copper-plating apparatus beingconfigured such that (i) the plating tank is partitioned by an anionexchange membrane into a cathode room and an anode room, and (ii) aninert electrode is provided for functioning as the anode electrode.Further, in the plating apparatus according to Document 4, the cathoderoom and the anode room are separated by the anion exchange membrane,and a cathode liquid and an anode liquid are supplied to the cathoderoom and the anode room, respectively.

With regard to the face-down type fountain plating apparatus among theabove conventional plating apparatuses, there has not been suggested aplating apparatus with which the plating solution would not becontaminated with micro foreign solid particles originated from, forexample, a black film.

SUMMARY OF THE INVENTION

In view of the above problems, the present invention has as an object toprovide (i) a plating apparatus, especially a face-down type fountainplating apparatus, with which the plating quality would not be degradedby micro foreign solid particles originated from, for example, a blackfilm, while maintaining the operability of the apparatus, (ii) a platingmethod, and (iii) a method for manufacturing a semiconductor device.

In order to solve the above problems, a plating apparatus according tothe present invention is adapted so that, in a plating apparatus forplating a plating-target face of a plating-target substrate, the platingapparatus including a plating tank in which an anode electrode isprovided, the plating apparatus performing the plating by (i) streaminga plating solution and an electrolytic liquid into the plating tank,(ii) emitting a jet of the plating solution to the plating-target faceof the plating-target substrate from an underneath of the plating-targetsubstrate, and (iii) streaming the electrolytic liquid to the anodeelectrode provided in the plating tank while electrically conductingbetween the plating-target substrate and the anode electrode, theplating tank including a partition in between the plating-targetsubstrate and the anode electrode, and the partition (i) separating theplating-target substrate and the anode electrode and (ii) dividing theplating tank into a plating-target substrate room and an anode electroderoom.

The plating apparatus according to the present invention performs theplating by streaming a plating solution and an electrolytic liquid intothe plating tank, and electrically conducting between the anodeelectrode and the plating-target substrate. Further, the platingapparatus of the present invention adopts the face-up method in whichjets of the plating solution are brought into contact with theplating-target face of the plating-target substrate from the underneaththereof. In this case, the electrolytic liquid streams into the anodeelectrode.

Note that the “plating-target substrate room” is the part of the spacedivided by the partition, which includes the plating-target substrate,whereas the “anode electrode room” is the part of the space divided bythe partition, which part includes the anode electrode.

In the above structure, the anode electrode and the plating-targetsubstrate are separated by the partition, and the plating tank isdivided into the plating-target substrate room and the anode electroderoom. This prevents the plating-target face from being contaminatedwith, for example, particles originated from the anode electrode.

As the foregoing described, with the above structure, it becomespossible to provide a plating apparatus with which the plating qualitywould not be degraded by the micro foreign solid particles originatedfrom, for example, black film, while maintaining the operability of theapparatus. Further, with the above structure, it becomes possible toprovide a high-density highly-precise semiconductor device havinghigh-quality plating for wiring.

In the plating apparatus of the present invention, an exemplarystructure in which “the plating solution is jet from an underneath ofthe plating-target substrate so that the plating solution is broughtinto contact with the plating-target face of the plating-targetsubstrate, and a voltage is applied in between the plating-targetsubstrate and the anode electrode while streaming the electrolyticliquid to the anode electrode” is that in which a plating solution jettube for emitting a jet of the plating solution to the plating-targetface of the plating-target substrate is provided in such a way that (i)the plating solution jet tube passes through the partition and (ii) theplating solution streams only into the plating-target substrate room.

This makes it possible to bring the plating solution into contact withthe plating-target face of the plating-target substrate from theunderneath thereof.

Another exemplary structure is that provided with an electrolytic liquidsupply tube for streaming the electrolytic liquid only into the anodeelectrode room. This makes it possible to stream the electrolytic liquidinto the anode electrode.

Normally, various additive agents are added to a plating solution usedfor plating. The additive agents are categorized into, roughly, (i) thesubstances that work in relation to the plating-target face of theplating-target substrate and (ii) the substances that work in relationto the surface of the anode electrode. The substances that work inrelation to the plating-target face of the plating-target substrategenerate, for example, a decomposition reaction on the surface of theanode electrode, generating a reaction product. This reaction productnegatively affects the reactions in plating. The “electrolytic liquid”indicates a solution containing none of the substances that work inrelation to the plating-target face of the plating-target substrate. Inthe above structure, the electrolytic liquid streams into the anodeelectrode room while the plating solution streams into theplating-target substrate room, and the anode electrode room and theplating-target substrate room are separated by the partition. Therefore,no decomposition reactions would be generated on the surface of theanode electrode, and the reactions in plating would not be negativelyaffected.

In order to solve the above problems, the method for manufacturing asemiconductor device, which method accords to the present invention,adapts the plating apparatus.

This makes it possible to provide a semiconductor device havinghigh-quality plating for wiring without any adhering micro foreign solidparticles originated from, for example, a black film on the surface ofthe anode electrode.

Further, in order to solve the above problems, the plating method of thepresent invention for plating a plating-target face of a plating-targetsubstrate includes the plating steps of: (i) streaming a platingsolution and an electrolytic liquid into a plating tank, (ii) emitting ajet of the plating solution to a plating-target substrate from anunderneath of the plating-target substrate, and (iii) streaming theelectrolytic liquid to an anode electrode provided in the plating tankwhile electrically conducting between the plating-target substrate andthe anode electrode; and plating the plating-target substrate in theplating tank in which a plating-target substrate and an anode electrodeare separated by a partition so that the plating tank is divided into aplating-target substrate room and an anode electrode room.

In the above configuration, the plating is performed by separating theanode electrode and the plating-target face in the plating tank, anddividing the plating tank into the plating-target substrate room and theanode electrode room. This prevents the plating-target face from beingcontaminated with particles originated from the anode electrode.

Additional objects, features, and strengths of the present inventionwill be made clear by the description below. Further, the advantages ofthe present invention will be evident from the following explanation inreference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross sectional diagram schematically illustrating astructure of a plating tank provided to a plating apparatus according toone embodiment of the present invention.

FIG. 2 is a cross sectional diagram illustrating an exemplary structureof a wafer holder of the plating tank.

FIG. 3 are a set of diagrams illustrating a structure of an areasurrounded by an inner tube and a partition in the plating tank. Theupper diagram is a diagram observing from a top of a plating-target faceof a semiconductor wafer, and the lower diagram is a cross sectionaldiagram of the area.

FIG. 4 is an explanatory diagram illustrating a structure of an ionexchange membrane.

FIG. 5 is an explanatory diagram illustrating selective permeability ofthe ion exchange membrane.

FIG. 6 is a diagram schematically illustrating a structure of a platingapparatus according to one embodiment of the present invention.

FIG. 7 is a schematic diagram illustrating a structure of thesemiconductor wafer.

FIG. 8(a) is a plane-view diagram schematically illustrating asemiconductor chip formed on the semiconductor wafer, at the time aftera plating step is performed.

FIG. 8(b) is a cross sectional diagram schematically illustrating asemiconductor chip formed on the semiconductor wafer, at the time afterthe plating step is performed.

FIG. 9 is a cross sectional diagram schematically illustrating a platingtank provided to a plating apparatus according to another embodiment ofthe present invention.

FIG. 10 is a diagram schematically illustrating a structure of a platingapparatus according to another embodiment of the present invention.

FIG. 11 is a cross sectional diagram schematically illustrating astructure of a conventional face-down type fountain plating apparatus.

FIG. 12 is a cross sectional diagram schematically illustrating astructure of a conventional rack-method vertical plating apparatus.

FIG. 13(a) is a cross sectional diagram illustrating a process of amethod for producing a semiconductor wafer, which method accords to thepresent embodiment. The cross sectional diagram schematicallyillustrates a part of a semiconductor chip at the time before the stepof forming a seed layer is performed.

FIG. 13(b) is a cross sectional diagram illustrating the process of themethod for producing the semiconductor wafer, which method accords tothe present embodiment. The cross sectional diagram schematicallyillustrates a part of the semiconductor chip at the time after the stepof forming a seed layer is performed.

FIG. 13(c) is a cross sectional diagram illustrating the process of themethod for producing the semiconductor wafer, which method accords tothe present embodiment. The cross sectional diagram schematicallyillustrates a part of the semiconductor chip at the time after the stepof applying a photoresist is performed.

FIG. 13(d) is a cross sectional diagram illustrating the process of themethod for producing the semiconductor wafer, which method accords tothe present embodiment. The cross sectional diagram schematicallyillustrates a part of the semiconductor chip at the time after the stepof forming a pattern on the photoresist is performed.

FIG. 13(e) is a cross sectional diagram illustrating the process of themethod for producing the semiconductor wafer, which method accords tothe present embodiment. The cross sectional diagram schematicallyillustrates a part of the semiconductor chip at the time after theplating step is performed.

FIG. 13(f) is a cross sectional diagram illustrating the process of themethod for producing the semiconductor wafer, which method accords tothe present embodiment. The cross sectional diagram schematicallyillustrates a part of the semiconductor chip at the time after the stepof removing is performed.

FIG. 13(g) is a cross sectional diagram illustrating the process of themethod for producing the semiconductor wafer, which method accords tothe present embodiment. The cross sectional diagram schematicallyillustrates a part of the semiconductor chip at the time after the stepof etching is performed.

FIG. 14(a) is a cross sectional diagram illustrating a process ofmounting an external connection terminal on a semiconductor wafer with awiring plated-layer formed thereon. The cross sectional diagramschematically illustrates a part of the semiconductor chip with thewiring plated-layer, at the time before the step of forming an over coatlayer is performed.

FIG. 14(b) is a cross sectional diagram illustrating the process ofmounting the external connection terminal on the semiconductor waferwith a wiring plated-layer formed thereon. The cross sectional diagramschematically illustrates a part of the semiconductor chip after thestep of forming an over coat layer is performed.

FIG. 14(c) is a cross sectional diagram illustrating the process ofmounting the external connection terminal on the semiconductor waferwith a wiring plated-layer formed thereon. The cross sectional diagramschematically illustrates a part of the semiconductor chip after thestep of forming a pattern on an over coat layer is performed.

FIG. 14(d) is a cross sectional diagram illustrating the process ofmounting the external connection terminal on the semiconductor waferwith a wiring plated-layer formed thereon. The cross sectional diagramschematically illustrates a part of the semiconductor chip after thestep of forming an external connection terminal is performed.

DESCRIPTION OF THE EMBODIMENTS First Embodiment

The following describes one embodiment of the present invention, withreference to FIGS. 1 to 8(a) and 8(b).

FIG. 1 is a cross sectional diagram schematically illustrating astructure of a plating tank provided to a plating apparatus of thepresent embodiment. As illustrated in FIG. 1, a plating tank 100 isprovided with: a wafer holder 2 that holds a semiconductor wafer(plating-target substrate (substrate to be plated)) 1; a cup 3; aplating solution supply nozzle (plating solution jet tube) 4; an anodeelectrode 5; a supporting member 6 that supports the anode electrode 5;a partition 7; and an electrolytic liquid supply tube 8. The cup 3 isprovided with an inner tube 31 and an outer tube 32.

The inner tube (second cylinder cup) 31 and the outer tube (firstcylinder cup) 32 are containers each having a substantially cylindricalshape with an opening top. The outer diameter of the inner tube 31 is sodesigned as to be smaller than that of the outer tube 32. The outer tube32 has an opening bottom. At the center of the bottom part of the innertube 31 is provided an electrolytic liquid supply tube 8 through whichelectrolytic liquid is supplied to the anode electrode 5.

Further, as illustrated in FIG. 1, the partition 7 having adoughnut-shape is formed on the inner wall of the outer tube 32. Thepartition 7 is disposed on the upper part of the outer tube 32 so as toform a partition in the inner tube 31 and in the outer tube 32. In otherwords, the partition 7 is so disposed as to keep the semiconductor wafer1 separated from the anode electrode 5. This divides the plating tank100 into a plating-target substrate room and an anode electrode room.The “plating-target substrate room” in the plating tank 100 is an areasurrounded by the outer tube 32 and the partition 7, whereas the “anodeelectrode room” in the plating tank 100 is an area surrounded by theinner tube 31 and the partition 7. In the plating-target substrate roomis disposed a plating-target face (face to be plated) W of thesemiconductor wafer. Further, in the anode electrode room is disposedthe anode electrode 5.

Further, as illustrated in FIG. 1, the plating solution supply nozzle 4is provided. The plating solution supply nozzle 4 passes through a holein a center portion of the partition 7. The supporting member 6 isconnected to the inner tube 31, and allows electrolytic liquid to passtherethrough. On the supporting member 6, the anode electrode 5 isdisposed. The anode electrode 5 is placed above the lower end of theplating solution supply nozzle 4.

The partition 7 includes a hydrocarbon type cation exchange membrane,but is not limited to a particular type of partition as long as thepartition 7 includes a permeation member that is permeable to an ion ofthe electrolytic liquid around the anode electrode 5 and the supportingmember 6, which electrolytic liquid has streamed into the anodeelectrode room through the electrolytic liquid supply tube 8. Forexample, the partition 7 may include an ion exchange membrane, a neutralmembrane, a porous ceramics, or the like. Further, in the case in whichthe partition 7 includes a hydrocarbon type cation exchange membrane,either of the followings may be adopted as the hydrocarbon type cationexchange membrane: Selemion (registered trademark) (hydrocarbon typecation exchange membrane, manufactured by Asahi Glass Engineering Co.,Ltd.), or Neosepta CM-1 (registered trademark) (hydrocarbon type cationexchange membrane, manufactured by Astom Corporation). A concretestructure of the partition 7 will be described later.

The inner tube 31 and the outer tube 32, both of which are components ofthe cup 3, the plating solution supply nozzle 4, and the supportingmember 6 are all made of polypropylene. Further, the anode electrode 5is a dissoluble anode electrode made of copper mixed with phosphorus.Thus, this anode electrode 5 is dissoluble. It should be noted that themember, which is made of propylene in the present embodiment by way ofexample, is not limited particularly, as long as the member has stabledimensions and is resistant to the plating solution and to theelectrolytic liquid. For example, the inner tube 31, the outer tube 32,the plating solution supply nozzle 4, and the supporting member 6 may bemade of hard vinyl chloride.

Meanwhile, the ion exchange membrane of Document 2 acts as a bottomcovering member so as to have the anode electrode soaked in the platingsolution, which anode electrode acts as a top covering member in theface-up type apparatus. The object of providing the ion exchangemembrane is thus basically different from that of the present invention.

Further, in contrast to the plating apparatus according to Document 4,the plating apparatus of the present embodiment adopts the face-downmethod so that the operability of the plating apparatus improvessignificantly and mass-production of the apparatus is facilitated.

Further, with the plating apparatus according to Document 2 that adoptsthe face-up method, the sample (plating-target substrate) cannot beremoved until the plating solution is completely drained out of theplating room. If the plating-target face is soaked in the platingsolution while no voltage is applied, then the metal ion is dissolvedagain. On the other hand, with the plating apparatus of the presentembodiment that adopts the face-down method, the sample (plating-targetsubstrate) can be removed immediately after the plating is finished.This improves (i) productivity in mass-production and (ii) the platingquality.

Normally, various additive agents are added to a plating solution usedfor plating. The additive agents are categorized into, roughly, (i) thesubstances that work in relation to the plating-target face of theplating-target substrate and (ii) the substances that work in relationto the surface of the anode electrode. The substances that work inrelation to the plating-target face of the plating-target substrategenerate, for example, a decomposition reaction on the surface of theanode electrode, generating a reaction product. This reaction productnegatively affects the reactions in plating.

Further, it is preferable that the plating solution contain copper. Itis also preferable that the plating solution be a conductive liquid.

By using the plating solution containing copper as the plating solution,the plating-target face of the plating-target substrate is plated withcopper. Further, the plating quality would be desirable especially whenthe plating is performed using a plating solution containing copper atthe ratio of: 14 g to 40 g of copper with respect to 1 L of platingsolution.

Further, it is preferable that the anode electrode be a dissoluble anodeelectrode made of copper containing phosphorus in a range of 0.04% to0.06%.

If an anode electrode made of pure copper is used as the anodeelectrode, an increased amount of foreign particles is generated.However, in the above structure, the anode electrode is a dissolubleanode electrode made of copper mixed with phosphorus, and therefore ablack membrane called a black film is formed on the surface of the anodeelectrode, which black film traps a copper complex ion (Cu⁺) that causesformation of the foreign particles.

Further, in order to prevent adhesion of micro foreign solid particlesoriginated from, for example, a black film, the conventional structuresare required to utilize an inert electrode. This causes a problem inthat the consumption of additive agents increases due to oxidativedecomposition of additive agent contained in the plating solution.Another problem is that the oxidative decomposition may generate adecomposition product, and the decomposition product would contaminatethe plating solution. This degrades the plating quality.

The “electrolytic liquid” is a solution containing none of thesubstances that work in relation to the plating-target face of theplating-target substrate. In the above structure, the electrolyticliquid streams into the anode electrode room while the plating solutionstreams into the plating-target substrate room, and the anode electroderoom and the plating-target substrate room are separated by thepartition. Therefore, no decomposition reactions would be generated onthe surface of the anode electrode, and the reactions in plating wouldnot be negatively affected.

Even if a substance that negatively affects the plating is generated inthe electrolytic liquid, the plating-target face would not be affectedbecause the plating-target face is isolated by the partition.

Concretely, the electrolytic liquid is a solution containing no metalthat is to be plated (for example, in the case of copper plating, themetal would be copper). On the other hand, the plating solution is asolution containing metal that is to be plated. Further, theelectrolytic liquid and the plating solution are common in that both ofthem have a conductive properties.

More specifically, if a solution containing copper sulfate is used asthe plating solution, then the electrolytic liquid is either sulfuricacid or an aqueous solution diluted with sulfuric acid.

Further, with the present invention, adhesion of micro foreign solidparticles generated from, for example, a black film is prevented, evenif the electrolytic liquid is either a solution containing metal that isthe type of metal to be plated or a solution that is identical to theplating solution. Even if a substance that negatively affects theplating is generated, the plating-target face would not be affectedbecause the plating-target face is isolated by the partition.

In other words, the electrolytic liquid may contain a copper. Further,the electrolytic liquid may be a conductive liquid.

Further, the electrolytic liquid may contain a copper at the ratio of:14 g to 40 g of copper with respect to 1 L of electrolytic liquid.

The applicable dimensions of the semiconductor wafer 1 in the presentembodiment may be set arbitrarily depending upon the dimensions of themembers of the plating tank 100. In the following, exemplary dimensionsapplicable in the present embodiments are described. A semiconductorwafer with a diameter of approximately 100 mm to 300 mm may be used asthe semiconductor wafer 1. More concretely, a semiconductor wafer with adiameter of approximately 150 mm may be used.

Further, the inner tube 31 has a cylindrical shape with an outerdiameter of 130 mm, an inner diameter of 120 mm, a thickness of 5 mm,and a height of 110 mm.

Further, the supporting member 6 is disposed in between the inner tube31 and the plating solution supply nozzle 4. The supporting member 6 isdisposed 20 mm, or at least 5 mm, above the bottom face of the innertube 31. Further, the supporting member 6 has numerous vertical throughholes.

On an upper part of the outer tube 32, a partition 7 is closely andfixedly attached. Further, the height of the outer tube 32 may be 30 mmor longer. Further, in FIG. 1, the lower end of the outer tube 32 ispositioned upper (i.e., closer to the plating-target substrate) than thelower end of the inner tube 31 is. The lower end of the outer tube 32,however, is not limited to the above case, and the lower end of theouter tube 32 may be lower than the lower end of the inner tube 31.Further, the inner diameter of the outer tube 32 is set, but notlimited, to 140 mm.

Further, with the plating tank 100, the height of the inner tube 31 isset, but not limited, to 110 mm, and the width of a gap between thepartition 7 and the upper end of the inner tube 31 is set, but notlimited, to 5 mm. The height and the width are set so that theelectrolytic liquid is sufficiently in contact with the periphery on thesurface of the partition 7.

Further, the partition 7 has a doughnut-shape with an outer diameter of140 mm and an inner diameter of 20 mm. The outer wall of the partition 7is closely attached to the outer tube 32, while the plating solutionsupply nozzle 4 is closely attached to the inner wall. By this, thepartition 7 is fixedly held. The dimensions of the partition 7 are notlimited to the above dimensions. Further, in a case that the partition 7is made of a product manufactured by Selemion, the thickness may beapproximately 100 μm, or between 100 μm and 200 μm.

Further, the dimensions of the anode electrode 5 made of copper mixedwith phosphorus are set, but not limited, to: 110 mm for the outerdiameter, 30 mm for the inner diameter, and the 8 mm for the thickness.The dimensions of the anode electrode 5 may be set arbitrarily in such away that the streams of the electrolytic liquid through the (i) gapbetween the supporting member 6 and the partition 7 and (ii) the gapbetween the inner tube 31 and the anode electrode 5 are not disturbed.

The plating solution supply nozzle 4 passes through the partition 7, andthe top end of the plating solution supply nozzle 4 is set to be 2 mmabove the partition 7. The plating solution supply nozzle 4 is not,however, limited to this structure and may be disposed arbitrarily,provided that the plating solution supply nozzle 4 reaches the partition7 and is closely fixed on the partition 7.

The foregoing described the respective dimensions of the components ofthe plating tank 100, which components include the semiconductor wafer1, the cup 3 (inner tube 31 and outer tube 32), the plating solutionsupply nozzle 4, the anode electrode 5, the supporting member 6, and thepartition 7. The respective dimensions of the components of the platingtank 100, however, may be set arbitrarily depending upon (i) thedimensions of the plating tank 100 or (ii) the dimensions of asemiconductor wafer 1 to be used.

The following concretely describes the wafer holder 2 that holds thesemiconductor wafer 1, with reference to FIG. 2. FIG. 2 is a crosssectional diagram illustrating a structure of the wafer holder 2 of theplating tank 100. As illustrated in FIG. 2, the wafer holder 2 isprovided with an O-ring 21, a contact member 22, and a wafer holder ring23. The wafer holder ring 23 is held by a holding member (notillustrated) with a certain distance between wafer holder ring 23 andthe upper end of the outer tube 32. The O-ring 21 and the contact member22 are provided on the wafer holder ring 23 so as to ensure closecontact with the semiconductor wafer 1 being held.

Further, three contact members 22 are disposed on the edge of thesemiconductor wafer 1. The three contact members 22 are equallydistanced from each other. The number of the contact members 22,however, is not limited to three. Alternatively, four or more contactmembers 22 may be disposed on the edge of the semiconductor wafer 1 andmay be equally distanced from each other. Further, a contact member 22having that is in contact with the whole edge may be providedalternatively.

The inner diameter of the wafer holder ring 23 is set, but not limited,to 140 mm. The shape of the wafer holder ring 23, obviously, does nothave to be a circle, and the wafer holder ring 23 may constitute a partof the casing of the apparatus. Further, the return tube 10 is providedon a part of the outer tube 32.

The following describes the respective members of the wafer holder 2.

The O-ring 21 is not limited particularly, as long as it ensures theclose contact with the semiconductor wafer 1 and is resistant to theplating solution. For example, a silicone rubber may be used for theO-ring 21. A concrete example thereof is Viton (registered trademark)(manufactured by DuPont Dow Elastomers Japan).

Further, the contact member 22 is not limited particularly, as long asit (i) ensures the close contact with the semiconductor wafer 1, (ii)has a conductive property, and (iii) is resistant to the platingsolution to be used. For example, a member that is made of titaniumplated with metal may be used. Concrete examples of the contact member22 include: a titanium plated with platinum; a titanium plated withgold; a resign plated with gold; and a combination of the above.

Furter, the wafer holder ring 23 is not limited particularly, as long as(i) the dimensions of the wafer holder ring 23 would not change and (ii)the wafer holder ring 23 is resistant to the plating solution to beused. Examples of the wafer holder ring 23 include: a ring made of hardvinyl chloride; and a ring made of polypropylene.

The following describes a structure of the partition 7 provided, to theplating tank 100, between (i) the plating-target face W of thesemiconductor wafer 1 and (ii) the anode electrode 5, with reference toFIG. 3. FIG. 3 illustrates a structure of the area (plating-targetsubstrate room) surrounded by the outer tube 32 and the partition 7 inthe plating tank 100. The upper diagram of FIG. 3 is a diagram observingfrom the top of the plating-target face W of the semiconductor wafer 1,whereas the lower diagram of FIG. 3 is a cross sectional diagramthereof.

As illustrated in FIG. 3, the partition 7 has a doughnut-shape whenobserved from the plating-target face W. At the center portion of thepartition 7, the plating solution supply nozzle 4 penetrates. Further,the outer edge of the partition 7 is fixed on the upper end portion ofthe outer tube 32.

Further, the partition 7 is provided with a semipermeable membrane(permeation member) 71 and semipermeable membrane supporting members 72and 73. The partition 7 has such a structure that the semipermeablemembrane supporting members 72 and 73 sandwich the semipermeablemembrane 71. The semipermeable membrane supporting member 72 is disposedon the side that faces toward the anode electrode 5, while thesemipermeable membrane supporting member 73 is disposed on the side thatfaces toward the plating-target face W of the semiconductor wafer 1.

Therefore, electrical conduction between the semiconductor wafer 1 andthe anode electrode 5 causes the electrolytic liquid to pass through thesemipermeable membrane supporting member 72, the electrolytic liquidhaving streamed to the anode electrode 5 (anode electrode room).Subsequently, an ion contained in the electrolytic liquid passes throughthe semipermeable membrane 71, and then pass through the semipermeablemembrane supporting member 73. Consequently, the ion reaches to theplating-target face W (plating-target substrate room) of thesemiconductor wafer 1. Note that the semipermeable membrane 71 ispermeable to only the ion contained in the electrolytic liquid, but isnot permeable to particles contained in the electrolytic liquid. Thisenables the partition 7 to separate the particles contained in theelectrolytic liquid, and therefore prevents the plated face from beingcontaminated with the particles originated from the anode electrode 5.

The semipermeable membrane 71 is not limited particularly, as long as itis permeable to the ion of the electrolytic liquid when being soaked inthe electrolytic liquid. Examples of the semipermeable membrane 71include: a hydrocarbon type cation exchange membrane; a neutralmembrane; and a porous ceramics. Further, concrete examples of thesemipermeable membrane 71 in the case where the semipermeable membrane71 is the hydrocarbon type cation exchange membrane include: Selemion(registered trademark) (hydrocarbon type cation exchange membrane,manufactured by Asahi Glass Engineering Co., Ltd.), and Neosepta CM-1(registered trademark) (hydrocarbon type cation exchange membrane,manufactured by Astom Corporation).

The semipermeable membrane supporting members 72 and 73 are not limitedparticularly, as long as they (i) transmit the electrolytic liquid, (ii)ensures the stability of dimensions, and (iii) is resistant to theplating solution. The semipermeable membrane supporting members 72 and73 may be made of polypropylene, or hard vinyl chloride, for example.

The following describes a structure of the semipermeable membrane 71,explaining, as an example, an ion exchange membrane including an ionexchange resin. FIG. 4 is an explanatory diagram illustrating astructure of the ion exchange membrane, and FIG. 5 is an explanatorydiagram illustrating selective permeability of the ion exchangemembrane.

As illustrated in FIG. 4, the “ion exchange membrane” is a membrane thatis selectively permeable to an ion. The ion exchange membrane iscategorized into, roughly, a cation exchange membrane and an anionexchange membrane. As illustrated in FIG. 4, when the electrolyticliquid is electrically conducted while the cation exchange membrane issoaked in the plating solution, the cation exchange membrane selectivelypasses cations (M+) therethrough but not anions (B−).

As illustrated in FIG. 5, an exchange group of negative electric chargeis fixed in the cation exchange membrane. The exchange group of negativeelectric charge repels the anions (B−), and therefore the anions (B−)cannot pass through the cation exchange membrane. On the other hand, theexchange group of negative electric charge does not repel the cations(M+), and therefore the cations (M+) pass through the cation exchangemembrane. In other words, only the cations (M+) can pass through thecation exchange membrane.

In contrast, the anion exchange membrane acts in an opposite manner asto the manner described above. In both cases, the ion exchange membranesconduct the selective permeation using a current power energy of anelectrodialyzer.

The following describes a structure of a plating apparatus of thepresent embodiment, with reference to FIG. 6. FIG. 6 is a diagramschematically illustrating the structure of the plating apparatus of thepresent embodiment.

As illustrated in FIG. 6, the plating apparatus of the presentembodiment is provided with: a plating tank 100 for plating theplating-target face W of the semiconductor wafer 1; a plating solutionsystem 20 that circulates the plating solution within the platingapparatus; and an electrolytic liquid system 30 that circulates theelectrolytic liquid within the plating apparatus.

The plating solution system 20 is provided with: a solution storage tank9 that functions as a plating solution supply source; an outer tube 32;a return tube 10 connected to a part of the outer tube 32; a platingsolution pump 101 for circulating the plating solution within theplating apparatus; a plating solution filter 111 that filters offforeign solid particles contained in the plating solution; and a pipe Tthat connects the above components.

The electrolytic liquid system 30 is provided with: an electrolyticliquid tank 22 including the members (wafer holder 2, cup 3, and memberssurrounded by the wafer holder 2 and the cup 3) provided in the platingtank 100; an electrolytic liquid storage tank 23 that functions as anelectrolytic liquid supply source; an electrolytic liquid pump 102 thatcirculates the electrolytic liquid within the plating apparatus; anelectrolytic liquid filter 112 that filters off the foreign solidparticles contained in the electrolytic liquid; and a pipe T′ thatconnects these components.

The following describes (i) a stream path of the plating solution and(ii) a stream path of the electrolytic liquid, in the plating apparatusof the present embodiment.

In the plating solution system 20, the plating solution pump 101 conveysthe plating solution stored in the plating solution storage tank 9 tothe plating solution supply nozzle 4 of the plating tank 100 via theplating solution filter 111. The plating solution then streams into theplating-target substrate room (area surrounded by the partition 7 andthe outer tube 32) of the plating tank 100, and reaches theplating-target face W of the semiconductor wafer 1. Subsequently, theplating solution streams into the return tube 10 provided on an upperedge of the outer tube 32. After that, the plating solution is returnedto the plating solution storage tank 9.

In the electrolytic liquid system 30, the electrolytic liquid pump 102conveys the electrolytic liquid stored in the electrolytic liquidstorage tank 23 to the electrolytic liquid supply tube 8 of the platingtank 100 via the electrolytic liquid filter 112. The electrolytic liquidthen streams into the anode electrode room (area surrounded by thepartition 7 and the inner tube 31). Then, at the partition 7, an ioncontained in the electrolytic liquid passes through the partition 7 andenters into the plating-target substrate room, whereas a black film thatis originated from the anode electrode and contained in the electrolyticliquid does not pass through the partition and thus does not enter intothe plating-target substrate room. As a result, a conduction state isrealized, and the plating is performed.

The electrolytic liquid streamed into the anode electrode room isdrained out of the plating tank 100 from an upper edge (gap between theinner tube 31 and the outer tube 32) of the inner tube 31. Theelectrolytic liquid then streams into the electrolytic liquid tank 22,and is returned to the plating solution storage tank 23.

The plating solution storage tank 9 and the pipe T in the platingsolution system 20 are not limited to a particular type, as long as (i)the dimensions of the tank and the pipe would not change and (ii) thetank and the pipe are resistant to the plating solution to be used. Thetank and the pipe may be made of, for example, hard vinyl chloride orpolypropylene. Further, the electrolytic liquid tank 22, theelectrolytic liquid storage tank 23, the electrolytic liquid filter 112,and the pipe T′ in the electrolytic liquid system 30 are not limited toparticular types, as long as (i) the dimensions of the tank and the pipewould not change and (ii) the tank and the pipe are resistant to theplating solution to be used. These components may be made of, forexample, hard vinyl chloride or polypropylene.

Further, the plating solution pump 101 in the plating solution system 20is not limited to a particular pump, as long as the pump is (i)resistant to the plating solution to be used and is (ii) capable ofconveying the plating solution without providing a negative influencethereon. Examples of the plating solution pump 101 include: MagneticPump MD-30R manufactured by IWAKI Co., Ltd.; and Magnetic Pump MD-6 toMD-70R manufactured by IWAKI Co., Ltd.

Further, the electrolytic liquid pump 102 in the electrolytic liquidsystem 30 is not limited to a particular pump, as long as the pump is(i) resistant to the electrolytic liquid to be used and is (ii) capableof conveying the electrolytic liquid without providing a negativeinfluence thereon. Examples of the electrolytic liquid pump 102 include:Magnetic Pump MD-70R manufactured by IWAKI Co., Ltd.; and Magnetic PumpMD-30 to MD-100R manufactured by IWAKI Co., Ltd.

Further, the plating solution filter 111 and the electrolytic liquidfilter 112 are not limited to a particular type of filter, as long asthe filter (i) thoroughly (100%) filters off particles of diameters ofapproximately a half of a targeted minimum interval of a platingpattern, (ii) is resistant to the plating solution (or electrolyticliquid) to be used, and (iii) provides no negative influence on theplating solution (or electrolytic liquid). Examples of the platingsolution filter 111 and the electrolytic liquid filter 112 include: afilter cartridge HDC (registered trademark) II made of polypropylene,manufactured by Nihon Pall Ltd. (J012; this thoroughly filters off allgrains each having a diameter of 1.2 μm); a filter cartridge HDC(registered trademark) II made of polypropylene, manufactured by NihonPall Ltd. (J006; this thoroughly filters off all grains each having adiameter of 1.0 μm); a filter made of Teflon (registered trademark), anda hollow fiber membrane filter.

To the respective pipes T and T′, a valve, a flowmeter, and an airoutlet tube are connected, although these components are not illustratedin FIG. 6. The stream of the plating solution can be controlled by acontroller (not illustrated). A voltage can be applied in between theplating-target face and the anode electrode by a power source (notillustrated) so that the plating is performed.

The following describes the semiconductor wafer 1, which functions asthe plating-target substrate in the present embodiment, with referenceto FIG. 7. FIG. 7 is a schematic diagram illustrating a structure of thesemiconductor wafer 1 used in the present embodiment. Further, FIG. 8(a)is a plane view and 8(b) is a cross sectional view, both illustrating astructure of a semiconductor chip 41 formed on the semiconductor wafer 1at the time after the plating step is performed.

As illustrated in FIG. 7, on the surface of the semiconductor wafer 1are formed a plurality of semiconductor chips 41. Further, along theedge of the semiconductor wafer 1 is disposed a contact section 42. Viathe contact section 42 a plating seed layer (not illustrated) isexposed. The contact section 42 is for establishing a contact with thecontact member 22 illustrated in FIG. 2, so that electricity is suppliedtherethrough.

As illustrated in FIG. 8(a), on the semiconductor chip 41 is formed thephotoresist layer 18 with an arbitrary shape. Further, as illustrated inFIG. 8(b), a seed layer 19 is formed on the surface of the semiconductorchip 41 at the time after the plating step is performed. On the surfaceof the seed layer 19 are formed a wiring plated-layer 16 and aphotoresist layer 18. A pad 17 is disposed on a face of the seed layer19, which face is opposite to the face on which the wiring plated-layer16 and the photoresist layer 18 are formed. In the semiconductor chip41, the wiring plated-layer 16 and the pad 17 are electrically connectedto each other.

Second Embodiment

The following describes another embodiment according to the presentinvention, with reference to FIGS. 9 and 10. In the present embodiment,the differences between the present embodiment and the first embodimentdescribed above will be explained. Therefore, for the purpose ofconvenience, the members having the same functions as those explained inthe first embodiment are given the same reference numerals, andexplanations thereof are omitted.

FIG. 9 is a cross sectional diagram schematically illustrating astructure of a plating tank provided to the plating apparatus of thepresent embodiment. As illustrated in FIG. 9, the plating tank 200 isprovided with: a wafer holder 2 that holds a semiconductor wafer(plating-target substrate (face to be plated)) 1; a cup 3; a platingsolution supply nozzle 4; an anode electrode 5; a supporting member 6that supports the anode electrode 5; a partition 7; an electrolyticliquid supply tube 8; an upper covering member 28; and an O-ring 29. Thecup 3 is provided with an inner tube 31 and an outer tube 32.

As illustrated in FIG. 9, the plating tank 200 of the plating apparatusof the present embodiment has the same structure as that of the firstembodiment except that an upper covering member 28 and an O-ring 29 areprovided. The upper covering member 28 and the O-ring 29 function asmeans for closing the plating-target substrate room. The followingexplains the upper covering member 28 and the O-ring 29. Description ofthe dimensions and structures of the following components provided tothe plating tank 200 is omitted because they are the same as those ofthe first embodiment: a semiconductor wafer 1; a wafer holder 2; a cup 3(inner tube 31 and outer tube 32); a plating solution supply nozzle 4;an anode electrode 5; a supporting member 6; a partition 7; and anelectrolytic liquid supply tube 8.

As illustrated in FIG. 9, the upper covering member 28 is disposed alongthe edge of the outer tube 32. The O-ring 29 is disposed in between theouter tube 32 and the upper covering member 28 so as to ensure the closecontact with the outer tube 32.

The plating solution supplied to the plating solution supply nozzle 4reaches the plating-target face (face to be plated) W of thesemiconductor wafer 1. In the plating tank 200, the O-ring 29 ensuresthe close contact of the upper covering member 28 and the outer tube 32.In other words, the plating-target substrate room is closed (closedsystem). Therefore, after reaching the plating-target face W of thesemiconductor wafer 1, the plating solution streams into the return tube10, instead of draining out of the plating tank 200. Because theplating-target substrate room is closed, the plating solution that hasstreamed into the plating-target substrate room is shielded from theatmosphere outside of the plating tank 200. Accordingly, with theplating tank 200, the plating solution would not go out of the platingtank 200. This prevents the atmosphere from being contaminated with, forexample, evaporated plating solution or a mist of the plating solution.Further, a fluctuation in the ion concentration due to evaporation ofthe plating solution is also prevented.

The dimensions of the upper covering member 28 are not limited toparticular dimensions, as long as the plating-target substrate room canbe closed. Further, the dimensions of the upper covering member 28 maybe set arbitrarily depending upon the dimensions of the outer tube 32.

Further, the upper covering member 28 is made of polypropylene. Thematerial of the upper covering member 28, however, is not limited to aparticular material, as long as (i) the dimensions of the material wouldnot change and (ii) the material is resistant to the plating solution.For example, the upper covering member 28 may be made of hard vinylchloride.

Further, the material of the O-ring 29 is not limited to a particularmaterial, as long as the material (i) allows the O-ring 29 to closelyattach to the outer tube 32 and (ii) is resistant to the platingsolution to be used. For example, the O-ring 29 may be made of siliconerubber, or more concretely, Viton (registered trademark).

The following describes a structure of the plating apparatus of thepresent embodiment, with reference to FIG. 10. FIG. 10 is a diagramschematically illustrating a structure of the plating apparatus of thepresent embodiment.

As illustrated in FIG. 10, the plating apparatus of the presentembodiment is provided with: a plating tank 100 for plating theplating-target face W of the semiconductor wafer 1; a plating solutionsystem 20′ that circulates the plating solution within the platingapparatus; an electrolytic liquid system 30′ that circulates theelectrolytic liquid within the plating apparatus; and a replenishingliquid system 40 for (i) monitoring a concentration of the circulatingplating solution and (ii) replenishing a replenishing liquid dependingupon the concentration of the ion in the plating solution.

The plating solution system 20′ is provided with: a plating solutionstorage tank 9′ that functions as a plating solution supply source; aplating solution supply nozzle 4; a return tube 10 connected to a partof the outer tube 32; a plating solution pump 101 that circulates theplating solution within the plating apparatus; a plating solution filter111 that filters off the foreign solid particles contained in theplating solution; and a pipe T that connects the above components. Theplating solution system 20′ is different from the plating solutionsystem 20 of the plating apparatus of the first embodiment in that theplating solution storage tank 9′ has a covering member and is covered(closed system).

Further, the electrolytic liquid system 30′ is provided with: anelectrolytic liquid tank 22′ in which the members (the wafer holder 2,the cup 3, and a member surrounding them, and the upper covering member28) surrounded by the plating tank 200 are included; an electrolyticliquid storage tank 23′ that functions as an electrolytic liquid supplysource; an electrolytic liquid pump 102 that circulates the electrolyticliquid within the plating apparatus; an electrolytic liquid filter 112that filters off the foreign solid particles contained in theelectrolytic liquid; and a pipe T′ that connects the above components.The electrolytic liquid system 30′ is different from the electrolyticliquid system 30 of the plating apparatus of the first embodiment inthat the electrolytic liquid storage tank 23′ has a covering member andis closed (closed system). Further, in the electrolytic liquid system30′, the outer tube 32 is closely attached to the electrolytic liquidtank 22′ in such a way as to completely close the opening of theelectrolytic liquid tank 22′. In other words, the electrolytic liquidtank 22′ is covered (closed system).

Further, the replenishing liquid system 40 is provided with: areplenishment unit 24; a supply pump 25; a replenishing liquid tank 26having a covering member a sensor 27; and a pipe T″ that connects theabove components. The pipe T″ is connected to the plating solutionstorage tank 9′ of the plating solution system 20′. Further, the sensor27 detects an ion concentration of the plating solution stored in theplating solution storage tank 9′. Information of the ion concentrationof the plating solution, which information is obtained by the sensor 27,is transmitted, in the form of an electric signal, to the supply pump 25via the replenishment unit 24. The supply pump 25 replenishes, basedupon an instruction according to the electric signal, the replenishingliquid from the replenishing liquid tank 26 to the plating solutionstorage tank 9′.

In FIG. 10, the replenishing liquid system 40 is illustrated as onesystem line. The replenishing liquid system 40, however, is not limitedto the structure of the one system line. Alternatively, one system maybe provided for respective kinds of liquids of which the platingsolution is made, which liquid need to be controlled and replenished.Further, in place of the replenishing liquid tank 26 and the supply pump25, (i) a replenishing pipe for pure water and (ii) a valve may beprovided, which is controlled by the replenishment unit.

The following describes (i) a stream path of the plating solution and(ii) a stream path of the electrolytic liquid, in the plating apparatusof the present embodiment.

In the plating solution system 20′, the plating solution pump 101conveys the plating solution stored in the plating solution storage tank9′ to the plating solution supply nozzle 4 of the plating tank 200 viathe plating solution filter 111. The plating solution then streams intothe plating-target substrate room (area surrounded by the partition 7and the outer tube 32) of the plating tank 200, and reaches theplating-target face W of the semiconductor wafer 1. Subsequently, theplating solution streams into the return tube 10 provided on an upperedge of the outer tube 32. After that, the plating solution is returnedto the plating solution storage tank 9′.

At this time, the plating-target substrate room is in a closed state dueto the upper covering member 28, and therefore the plating solutionstreamed into the plating-target substrate room is shielded from theatmosphere. This prevents the atmosphere from being contaminated withevaporated plating solution or a mist of the plating solution. Moreover,a fluctuation in the ion concentration due to evaporation of the platingsolution is also prevented. Further, because the plating solutionstorage tank 9′ has a covering member and is covered, the platingsolution streamed into the plating solution storage tank 9′ is shieldedfrom the atmosphere. Therefore, with the plating apparatus, theatmosphere is prevented from being contaminated with evaporated platingsolution or a mist of the plating solution. Further, a fluctuation inthe ion concentration due to evaporation of the plating solution is alsoprevented.

In the electrolytic liquid system 30′, the electrolytic liquid pump 102conveys the electrolytic liquid stored in the electrolytic liquidstorage tank 23′ to the electrolytic liquid supply tube 8 of the platingtank 200 via the electrolytic liquid filter 112. The electrolytic liquidthen streams into the anode electrode room (area surrounded by thepartition 7 and the inner tube 31). Then, at the partition 7, an ioncontained in the electrolytic liquid passes through the partition 7 andenters into the plating-target substrate room, whereas a black film thatis originated from the anode electrode and contained in the electrolyticliquid does not pass through the partition and thus does not enter intothe plating-target substrate room. As a result, a conduction state isrealized, and the plating is performed.

The electrolytic liquid streamed into the anode electrode room isdrained out of the plating tank 200 from an upper edge (gap between theinner tube 31 and the outer tube 32) of the inner tube 31. Theelectrolytic liquid then streams into the electrolytic liquid tank 22′,and is returned to the plating solution storage tank 23′.

At this time, because the electrolytic liquid tank 22′ and theelectrolytic liquid storage tank 23′ are in a closed state, theelectrolytic liquid streamed into (i) the electrolytic liquid tank 22′and (ii) the electrolytic liquid storage tank 23′ are shielded from theatmosphere. This prevents the atmosphere from being contaminated withevaporated electrolytic liquid or a mist of the electrolytic liquid.Further, a fluctuation in the ion concentration due to evaporation ofthe electrolytic liquid is also prevented.

Description of the materials of the following components is omittedbecause they are the same as those of the first embodiment: the platingsolution storage tank 9′; the plating solution pump 101; the platingsolution filter 111; the pipe T; the electrolytic liquid tank 22; theelectrolytic liquid storage tank 23; the electrolytic liquid pump 102;the electrolytic liquid filter 112; and the pipe T′.

The material of the pipe T″ of the replenishing liquid system 40 is notlimited to a particular material, as long as the material (i) allows thedimensions of the pipe to remain unchanged and (ii) is resistant to thereplenishing liquid to be used. For example, the pipe T″ may be made ofhard vinyl chloride, polypropylene, or Teflon (registered trademark).

Further, the supply pump 25 is not limited particularly, as long as thepump is (i) resistant to the replenishing liquid to be used and (ii)capable of conveying the replenishing liquid to the plating solutionstorage tank 9′ without providing a negative influence on the platingsolution. Examples of the supply pump 25 include: Peristaltic PumpMP-1000 manufactured by Tokyo Rikakikai Co.; and Peristaltic PumpsMP-1000A to MP-1000B manufactured by Tokyo Rikakikai Co.

To the respective pipes T, T′, and T″, for example a valve, a flowmeter,and an air outlet tube are connected, although these components are notillustrated in FIG. 10. The stream of the plating solution can becontrolled by a controller (not illustrated). A voltage can be appliedin between the plating-target face and the anode electrode by a powersource (not illustrated) so that the plating is performed.

The plating apparatus according to the present invention can also bedescribed in the following way.

The plating apparatus according to the invention is a plating apparatusfor plating a substrate and is arranged such that (i) the electrolyticliquid system constituted by an anode electrode and an electrolyticliquid and (ii) the plating solution system constituted by aplating-target face and a plating solution are separated in the cup ofthe plating apparatus.

Further, in the plating apparatus, the plating solution streams into thearea formed by the plating-target substrate and the partition providedin the outer tube 32 of the plating cup.

Further, in the plating apparatus, the electrolytic liquid streams intothe area formed by the partition and the anode electrode provided in theinner tube 31 of the plating cup.

Further, the partition is provided so that the electrolytic liquidstreamed into the inner tube 31 of the plating cup would not reach theplating-target substrate.

Further, the electrolytic liquid streamed into the inner tube 31 of theplating cup is drained out of the cup.

The structure (partition) that separates the anode electrode and theplating-target substrate in the plating cup is partially or wholly madeof material that is permeable to an ion when soaked in the electrolyticliquid.

It is preferable that the material that (i) separates the anodeelectrode and the plating-target substrate in the plating cup and (ii)is permeable to an ion when soaked in the electrolytic liquid be asemipermeable membrane.

It is preferable that the material that (i) separates the anodeelectrode and the plating-target substrate in the plating cup and (ii)is permeable to an ion when soaked in the electrolytic liquid be an ionexchange membrane.

The plating apparatus according to the present invention is structuredin such a way that the plating solution system and the electrolyticliquid system are separated so as to be independent from each other.Therefore, contamination of the plating-target face due to the anodeelectrode is prevented.

Further, the plating apparatus according to the present invention isstructured in such a way that the plating solution system and theelectrolytic liquid system are separated so as to be independent fromeach other. Therefore, the plating quality of the plating-target facewould not be degraded by a decomposition of the additive agent in theplating solution due to the anode electrode.

Further, in the plating apparatus, the cup, the plating tank, the othertanks, and the pipes form a closed system so as to shield the platingsolution and the electrolytic liquid from the atmosphere. This preventsthe atmosphere from being contaminated with evaporated plating solutionor evaporated electrolytic liquid.

Further, in the plating apparatus, the cup, the plating tank, the othertanks, and the pipes form a closed system so as to shield the platingsolution and the electrolytic liquid from the atmosphere. This preventsa fluctuation in the concentration of the liquid due to evaporation ofthe liquids.

The plating solution is either a conductive liquid containing copper ora conductive liquid prepared by adding another substance to a conductiveliquid containing copper.

Further, the plating solution contains copper metal, and the proportionof the copper metal in 1 L of the plating solution is 14 g to 40 g,inclusive.

The anode electrode is a dissoluble anode electrode plate made of coppermixed with phosphorus by 0.04% to 0.06%.

Further, the electrolytic liquid is (i) sulfuric acid or (ii) an aqueoussolution in which sulfuric acid is diluted.

Further, the electrolytic liquid may be either a conductive liquidcontaining copper or a conductive liquid prepared by adding anothersubstance to a conductive liquid containing copper.

Further, it is preferable that (i) the electrolytic liquid containcopper metal and (ii) the proportion of the copper in 1 L ofelectrolytic liquid be 14 g to 40 g, inclusive.

In a semiconductor device according to the present invention, (i) theelectrolytic liquid system constituted by an anode electrode and anelectrolytic liquid and (ii) the plating solution system constituted bythe plating-target face and the plating solution are separated in thecup of the face-down type fountain plating apparatus utilized forplating a substrate.

Further, the plating solution is supplied to an area formed by (a) thepartition in the outer tube 32 of the plating cup and (b) a substratehaving a plating-target face. In the plating method including the stepsof (i) streaming the plating solution into the area formed by (a) thepartition in the outer tube 32 of the plating cup and (b) a substratehaving a plating-target face, (ii) bringing the plating solution intocontact with the plating-target face, (iii) electrically conductingbetween the plating-target face and the anode electrode provided in theplating cup, the partition prevents the electrolytic liquid streamedinto the inner tube 31 of the plating cup from reaching theplating-target face. Therefore, the foreign solid particles contained inthe electrolytic liquid would not adhere onto the plating-target face.

Further, in the plating method including the steps of (i) streaming theplating solution into the area formed by (a) the partition in the outertube 32 of the plating cup and (b) the substrate having a plating-targetface, (ii) bringing the plating solution into contact with theplating-target face, (iii) electrically conducting between theplating-target face and the anode electrode provided in the plating cup,the partition is permeable to only an ion contained in the electrolyticliquid streamed into the inner tube 31 of the plating cup. The rest ofthe electrolytic liquid is drained out of the cup.

The structure that separates the anode electrode and the plating-targetface in the plating cup is partially or wholly made of material that ispermeable to an ion when soaked in the electrolytic liquid.

The material that (i) separates the anode electrode and theplating-target face in the plating cup and (ii) is permeable to an ionwhen soaked in the electrolytic liquid is either a semipermeablemembrane or an ion exchange membrane.

The plating apparatus is structured in such a way that the platingsolution system and the electrolytic liquid system are separated so asto be independent from each other. Therefore, contamination of theplating-target face due to the anode electrode is prevented.

The plating apparatus is structured in such a way that the platingsolution system and the electrolytic liquid system are separated so asto be independent from each other. Therefore, the plating quality wouldnot be degraded by a decomposition of the additive agent contained inthe plating solution due to the anode electrode.

The plating apparatus is adapted so that the cup, the plating tank, theother tanks, and pipes form a closed system so as to shield the platingsolution and the electrolytic liquid from the atmosphere. This prevents(i) evaporation of the liquids, (ii) contamination of the atmosphere,and (iii) and fluctuation in the concentration of the liquids.

As a result, it becomes possible to provide (i) a semiconductor devicewith which the plating quality would not be degraded by micro foreignsolid particles originated from, for example, a black film, while theoperability of the face-down type fountain plating apparatus ismaintained and (ii) a method for manufacturing the semiconductor device.It is also possible to prevent the plating solution, the electrolyticliquid, or the like from evaporating or generating a mist.

As the foregoing described, the present invention has the followingeffects.

Plating solution from which the foreign solid particles have beenfiltered off is brought into contact with the plating-target face. Theplating-target face is separated, by the partition including an ionexchange membrane, from the electrolytic solution streamed into thevicinity of the anode electrode. Only copper ion passes through thepartition, reaches the plating-target face, and is deposited. Therefore,it becomes possible to provide a high-density and highly-precisesemiconductor device with a high-quality plating for wiring, withoutmicro foreign solid particles being adhered on the surface of the anodeelectrode, which particles are originated from, for example, a blackfilm.

Further, because it is not necessary to use an inert electrode, whichhas conventionally been adopted, to prevent micro foreign solidparticles from adhering, which particles originate from, for example, ablack film, an increase of the consumption of the additive agent due tooxidative decomposition of additive agent contained in the platingsolution can be prevented. Further, the plating quality would not bedegraded by a decomposition product contaminating the plating solution.Therefore, it becomes possible to provide a high-density andhighly-precise semiconductor device with a high-quality plating forwiring. Further, because the plating is performed in the closed system,the plating solution and the electrolytic liquid neither evaporate norgenerate mists, and the concentration remains unchanged and the cleansurrounding environment is maintained.

Third Embodiment

In the present embodiment, a method for manufacturing a semiconductorchip using a plating apparatus according to one of the first or thesecond embodiments will be explained in detail, with reference to FIGS.13(a) to 13(g), and FIGS. 14(a) to 14(d). FIG. 13 are cross sectionaldiagram illustrating the process of the method for manufacturing asemiconductor device according to the present embodiment. In the presentembodiment, as one example of the method for manufacturing asemiconductor device, a method for manufacturing the semiconductor chip41 illustrated in FIGS. 7, 8(a), and 8(b) will be explained.

As illustrated in FIGS. 13(a) to 13(g), the method for manufacturing thesemiconductor device according to the present embodiment includes thesteps of: forming a seed layer 19 on the surface of the semiconductorchip 41; applying a photoresist on the seed layer 19 thereby to form aphotoresist layer 18 thereon; forming an arbitrary pattern on thephotoresist layer 18; plating with metal according to the patternthereby to form a wiring plated-layer; removing the photoresist layer18; and etching the seed layer 19. FIG. 13(a) schematically illustratesa part of the semiconductor chip 41 at the time before the step offorming the seed layer is performed. FIG. 13(b) schematicallyillustrates a part of the semiconductor chip 41 at the time after thestep of forming the seed layer is performed. FIG. 13(c) schematicallyillustrates a part of the semiconductor chip 41 at the time after thestep of applying the photoresist is performed. FIG. 13(d) schematicallyillustrates a part of the semiconductor chip 41 at the time after thestep of forming the photoresist pattern is performed. FIG. 13(e)schematically illustrates a part of the semiconductor chip 41 at thetime after the step of plating is performed. FIG. 13(f) schematicallyillustrates a part of the semiconductor chip 41 at the time after thestep of removing is performed. Finally, FIG. 13(g) schematicallyillustrates a part of the semiconductor chip 41 at the time after thestep of etching is performed.

As illustrated in FIG. 13(a), a pad 17 that externally exchanges anelectric signal is provided on the surface of the semiconductor chip 41at the time before the seed layer is formed.

As illustrated in FIG. 13(b), in the step of forming a seed layer, theseed layer 19 is formed on the semiconductor chip 41. Specifically, asemiconductor wafer having the semiconductor chip 41 is placed in aspattering apparatus such that a seed layer is formed on the face wherethe pad is formed. Then, a titanium layer of 1000 Å thickness is formedon the surface of the semiconductor wafer, which titanium layerfunctions as a barrier metal. Subsequently, a copper layer of 300 Åthickness is formed. This copper layer functions as the seed layer 19used for plating. The seed layer 19 is a first core that facilitates thegrowth of plating material (wiring plated-layer 16) in the plating stepdescribed below.

In the above example, in the step of forming the seed layer, thetitanium layer is formed so as to function as the barrier metal. Thelayer to function as the barrier metal, however, is not limited to thetitanium layer, and may be a chromium layer. Alternatively, a layer madeof an alloy of titanium and tungsten may be used as the barrier metal.Any types of layer may function as the barrier metal, as long as thelayer is made of metal that provides a barrier effect.

Further, in the above case, the thickness of the titanium layer is 1000Å. The thickness, however, is not limited to that value, and thethickness may be 5000 Å or thicker, as long as the barrierness isensured. Further, the thickness of the copper layer that functions asthe seed layer 19 used for plating is 3000 Å, but the thickness is notlimited to that value; the thickness of the copper layer may be 1000 Åor greater, as long as the thickness ensures that the electric currentdensity is maintained at a constant level during the plating step.

As illustrated in FIG. 13(c), in the step of applying a photoresist, thephotoresist is applied on the semiconductor wafer (including thesemiconductor chip 41) thereby to form the photoresist layer 18, thesemiconductor wafer having the seed layer 19 thereon. In the step ofapplying the photoresist, a spin-coating apparatus spins thesemiconductor wafer 1 for 30 seconds at the velocity of 1500 spins perminute to coat the surface of the semiconductor wafer 1 with thephotoresist (PMER P-LA900, manufactured by Tokyo Ohka Kogyo Co., Ltd.).Then, the semiconductor wafer 1 is baked at 115° C. for 5 minutes.

In the above case, the PMER P-LA900 is used as the photoresist. Thephotoresist, however, is not limited to the product, as long as thephotoresist is resistant to the processes performed during the platingstep described below. For example, PMER N-CA3000, manufactured by TokyoOhka Kogyo Co., Ltd, may be used as the photoresist. Further, the methodof coating the photoresist is not limited to the spin-coating. Forexample, the photoresist layer 18 may be formed on the semiconductorwafer 1 by applying a dry film (e.g., ORDYL MP100 Series, manufacturedby Tokyo Ohka Kogyo Co., Ltd.) thereon.

Further, in the step of applying a photoresist application, thespin-coating apparatus spins the semiconductor wafer for 30 seconds atthe velocity of 1500 spins/minute to coat the photoresist on thesemiconductor wafer, and then the semiconductor wafer is baked at 115°C. for 5 minutes. The method of spin-coating, however, is not limited tothe above method. For example, the semiconductor wafer may be spun atthe velocity of 1000 spins to 3000 spins per minute until the thicknessof the photoresist becomes sufficiently uniformed, and then thesemiconductor wafer may be heated at 100° C. to 120° C. forapproximately 5 minutes.

As illustrated in FIG. 13(d), in the step of forming a photoresistpattern, an arbitrary pattern is formed on the photoresist layer 18 thathas been formed in the step of applying the photoresist. Specifically,after the step of applying the photoresist is performed, thesemiconductor wafer having the semiconductor chip 41 is placed in anexposure device (not illustrated). Then, the photoresist layer 18 isilluminated with a g-line (436 nm). Subsequently, the photoresist layer18 is developed by a development device (not illustrated) using2.38%-TMAH aqueous solution. Then, a corresponding portion of thephotoresist to the portion on which the plating for wiring is to beperformed is removed.

In the above case, the photoresist layer 18 is illuminated with theg-line (436 nm). The light beam to be illuminated on the photoresistlayer 18 during the exposure is not limited to a particular light beam,as long as the light beam can expose the photoresist. For example, ani-line (365 nm) or a deep UV (approximately 200 nm to 300 nm) may beilluminated on the photoresist layer 18. Further, in the step of formingthe photoresist pattern, the photoresist layer 18 is developed using the2.38%-TMAH aqueous solution. The concentration of the TMAH aqueoussolution, however, is not limited to the value. For example, theconcentration of the TMAH aqueous solution may be 1% to 3%.Alternatively, 25%-TMAH aqueous solution may be diluted with pure waterto a concentration that is suitable for the development.

As illustrated in FIG. 13(e), in the plating step, an exposed portion ofthe seed layer 19 is plated, which portion is exposed as a result thatthe arbitrary pattern is formed on the photoresist layer 18 in the stepof forming the photoresist pattern. In other words, after the step offorming a photoresist pattern is performed, the semiconductor waferhaving the semiconductor chip 41 is placed in the plating apparatusillustrated in FIG. 1. Specifically, the semiconductor wafer 1 is placedon the wafer holder 2 of the plating apparatus. Then, the O-ring 21 andthe contact member 22 are brought into close contact with the contactsection 42 of the semiconductor chip 41 by a wafer holding member (notillustrated).

The plating step adopts, as a step of the method for manufacturing asemiconductor device, the plating method performed by the platingapparatus according to the first embodiment or to the second embodiment.In other words, the method for manufacturing a semiconductor deviceaccording to the present embodiment adopts the plating apparatusaccording to the first embodiment or to the second embodiment.

The following describes an exemplary plating step in which the platingapparatus illustrated in FIG. 6 is utilized. The plating apparatus to beutilized in the plating step is not limited to the plating apparatusillustrated in FIG. 6.

In the plating step, the electrolytic liquid pump 102 operated by acontroller (not illustrated) transports dilute sulfuric acid(electrolytic liquid) to the electrolytic liquid filter 112 from theelectrolytic liquid storage tank 23 where the dilute sulfuric acid isstored. The amount transported is approximately 20 L per minute, 10 L to20 L per minute, or a sufficient amount for achieving the object. Atthis time, the electrolytic liquid stored in the electrolytic liquidstorage tank 23 contains sulfuric acid by approximately 200 g/L or in arange of 150 g/L to 250 g/L.

The foreign solid particles that are contained in the electrolyticliquid and are larger than the diameter of the filter opening arefiltered off and removed by the electrolytic liquid filter 112.Subsequently, the electrolytic liquid streams into the cup 3 via thepipe T′. Then, the electrolytic liquid entered from the bottom part ofthe inner tube 31 of the cup 3 streams into the area between thesupporting member 5 and the bottom of the inner tube 31. Theelectrolytic liquid streamed into the area between the supporting member5 and the bottom of the inner tube 31 (i) moves upward through thethrough holes of the supporting member and (ii) flows around the anodeelectrode. Then, the electrolytic liquid moves along the partition 7toward the edge of the cup 3. Subsequently, the electrolytic liquidpasses through the area between the inner tube 31 and the outer tube 32,is drained out of the cup to the electrolytic liquid tank 22, and isreturned to the electrolytic liquid storage tank 23. Note that the anodeelectrode 6 is made of copper mixed with phosphorus by 0.04% to 0.06%.

On the other hand, the plating solution stored in the plating solutionstorage tank 9 is transported to the plating solution filter 111 by theplating solution pump 101 operated by a controller (not illustrated).The amount to be transported is approximately 2 L per minute, 1 L to 2 Lper minute, or a sufficient amount for achieving the object. In thepresent embodiment by way of example, the plating solution stored in theplating solution storage tank 9 is a copper plating solution (microfabCu200, manufactured by Electroplating Engineers of Japan Ltd.)containing copper and an additive agent (not illustrated) and copper.The ratio of copper contained is approximately 25 g/L in conversion ofmetallic copper.

The foreign solid particles that are contained in the plating solutionand are larger than the diameter of the filter opening are filtered offby the plating solution filter 111. Then, the plating solution streamsinto the plating solution supply nozzle 4 via the pipe T. Subsequently,the plating solution streams into and fills in the area surrounded bythe semiconductor wafer 1 and the partition 7. Consequently, the surfaceof the plating solution is brought into contact with the plating-targetface W of the semiconductor wafer 1.

After being in contact with the plating-target face W of thesemiconductor wafer 1, the plating solution is drained out of the cup 3from the upper edge of the outer tube 32. Then, the plating solutionpasses through the return tube 10, which is provided on a part of theouter tube 32, and is returned to the plating solution storage tank 9.

At this time, if the plating-target face W of the semiconductor wafer 1is a cathode electrode, and a power source (not illustrated) for platingapplies a voltage in between the plating-target face W and the anodeelectrode 5 while controlling current, then a copper ion is generated onthe surface of the anode electrode 5. In this case, the generated copperion passes through the partition 7, and reaches, via the outer tube 32,the surface of the semiconductor wafer 1, which functions as the cathodeelectrode. Then, on the plating-target face W of the semiconductor wafer1, the copper ion reacts, in a predefined way, with the additive agentcontained in the plating solution, and is deposited as copper with thethickness of approximately 10 μm.

On the other hand, in the inner tube 31 is filled with the electrolyticliquid from which the foreign solid particles larger than the diameterof the filter opening have been removed by the electrolytic liquidfilter 112. The electrolytic liquid that have streamed in the vicinityof the anode electrode 5 is blocked by the partition 7 and thereforecannot stream into the outer tube 32; only the copper ion passes throughthe partition 7 and streams into the outer tube 32. Thus, micro foreignsolid particles originated from, for example, a black film on thesurface of the anode electrode would not adhere to the plating-target Wof the semiconductor wafer 1. Further, it is not necessary to use aninert electrode, which is used in a conventional apparatus in order toprevent the micro foreign solid particles originated from, for example,a black film from adhering. Therefore, (i) the consumption of theadditive agent due to oxidative decomposition of the additive agentcontained in the plating solution will not increase, and (ii) theplating solution will not be contaminated with a decomposition productand therefore the plating quality will not be degraded. Thus,high-quality plating is achieved.

Further, in the plating step, the electrolytic liquid is streamed intothe anode electrode room (area surrounded by the partition 7 and theinner tube 31), while the plating solution is streamed into theplating-target substrate room (area surrounded by the partition 7 andthe outer tube 32), thereby performing the plating process. Performingthe plating process with the electrolytic liquid and the platingsolution separated from one another allows reduction in the amount ofnecessary plating solution that is expensive. Further, in the case wherethe plating solution is decomposed or contaminated, the plating solutionin the plating apparatus needs to be replaced. With the plating step(plating method) according to the present invention, only a few amountof the plating solution needs to be replaced when the plating solutionis decomposed or contaminated.

The voltage to be applied in between the plating-target face W and theanode electrode 5 may be set arbitrarily depending upon the dimensionsof the semiconductor wafer 1 or the dimensions of the plating tank.Further, the application time of the voltage can also be arbitrarily setdepending upon the dimensions of the semiconductor wafer 1 or thedimensions of the plating tank. Specifically, the voltage is applied for25 minutes while controlling the electric current density of theplating-target face W is maintained at 20 mA per square centimeters, orat an ampere in a range of 10 mA per square centimeters to 50 mA persquare centimeters. The electric current density should be set to asufficient value for achieving the object.

In the present embodiment, copper plating solution (microfab Cu200,manufactured by Electroplating Engineers of Japan Ltd.) is used as theplating solution. The plating solution, however, is not limited to thecopper plating solution, and other plating solutions can also be used aslong as the plating solutions can provide the required functions. Forexample, Levco Ex, manufactured by Uyemura & Co., Ltd, can also be used.

Further, in the step of removing, as illustrated in FIG. 13(f), thephotoresist layer 18 formed on the semiconductor chip 41 after theplating step is removed. Specifically, the semiconductor wafer of FIG.13(e), which semiconductor wafer contains the semiconductor chip 41, isplaced in a removing apparatus (not illustrated). Then, thesemiconductor wafer is soaked in a stripping solution (104 strippingsolution, manufactured by Tokyo Ohka Kogyo Co., Ltd.) of 70° C. for 20minutes, and is shaken occasionally. As a result, the photoresist layer18 formed on the surface of the semiconductor wafer is removed.

The present invention is not limited to the step of removing, in whichthe semiconductor wafer 1 is soaked in the 104 stripping solution of 70°C. for 20 minutes, and is shaken occasionally. The soaking time is notlimited to the above time, and the soaking time may be, for example, 15minutes to 25 minutes. Further, R-100, manufactured by Mitsubishi GasChemical Company Inc., for example, may be used as the strippingsolution, and the semiconductor wafer 1 may be soaked in R-100 of 50° C.for 8 minutes to 15 minutes, and be concussed occasionally.Alternatively, acetone may be used as the stripping solution.

Subsequently, in the step of etching, as illustrated in FIG. 13(g), theetching process is performed to remove the seed layer 19 on which nowiring plated-layer 16 is formed. Specifically, the semiconductor wafer1 of FIG. 13(f), which semiconductor wafer 1 contains the semiconductorchip 41, is placed in an etching apparatus (not illustrated). Then, thesemiconductor wafer 1 is soaked in 10%-persulfuric acid ammonium aqueoussolution of 25° C. for one and a half minute, and is shaken, thereby toetch the seed layer 19 made of copper (Cu) other than the copper wiringplated section (wiring plated-layer 16), that is, the seed layer 19 onwhich no wiring plated-layer 16 is formed.

In the above case, during the step of etching, the semiconductor waferis soaked in 10%-persulfuric acid ammonium aqueous solution of 25° C.for one and a half minute, and is shaken. The aqueous solution, however,is not limited to the above solution, and other aqueous solutions, forexample 10%-sodium hydroxide aqueous solution or 40%-ferric chlorideaqueous solution, may be used as the aqueous solution. Further, thetemperature of the aqueous solution is not limited to the abovetemperature, and may be at a temperature in a range of 15° C. to 40° C.

Further, in the step of etching, subsequently, the semiconductor waferis soaked in 25%-TMAH of 90° C. for one hour, and is shaken, therebyetching the titanium layer (not illustrated) other than the copperwiring plated-section (wiring plated-layer 16), which titanium layerfunctions as the barrier metal. In other words, the titanium layer onwhich no wiring plated-layer 16 is formed is etched.

In the above case, the etching is performed by soaking the titaniumlayer in 25%-TMAH of 90° C. for one hour with shaking. The aqueoussolution used for etching the titanium layer, however, is not limited tothe above aqueous solution. For example, (i) hydrochloric acid or (ii) amixture of hydrofluoric acid and nitric acid.

On the semiconductor chip 41, on which the interconnect plated-layer 16has been formed, of the semiconductor wafer, an external connectionterminal is formed. The following describes the step of mounting anexternal connection terminal, with reference to FIGS. 14(a) to 14(d).FIGS. 14(a) to 14(d) are cross sectional diagrams illustrating the stepof mounting an external connection terminal. In the step, the externalconnection terminal 34 is mounted on the semiconductor chip 41 on whichthe wiring plated-layer 16 has been formed.

The step of mounting an external connection terminal includes the stepsof: forming an over coat layer on the surface of the semiconductor chip41 where the wiring plated-layer 16 has been formed; forming anarbitrary pattern on the over coat layer; and forming an externalconnection terminal on the wiring plated-layer 16 according to thepattern on the over coat layer. FIG. 14(a) schematically illustrates apart of the semiconductor chip 41 on which the wiring plated-layer 16 atthe time before the step of forming an over coat layer is performed.FIG. 14(b) schematically illustrates a part of the semiconductor chip 41at the time after the step of forming an over coat layer is performed.FIG. 14(c) schematically illustrates a part of the semiconductor chip 41at the time after the step of forming a pattern on the over coat layeris performed. Finally, FIG. 14(d) schematically illustrates a part ofthe semiconductor chip 41 at the time after the step of forming anexternal connection terminal.

As illustrated in FIG. 14(a), on the semiconductor chip 41 of thesemiconductor wafer 1, the seed layer 19 is formed below the wiringplated-layer 16 (with respect to the wiring plated-layer 16, the seedlayer 19 is formed on the side where the pad 17 is). The wiringplated-layer 16 is electrically connected, via the seed layer 19, to thepad 17 formed on the semiconductor chip 41.

As illustrated in FIG. 14(b), in the step of applying an over coatlayer, an over coat layer 33 is formed on the semiconductor waferincluding the semiconductor chip 41 on which the plating for wiringlayer 16 has been formed. Specifically, the over coat layer 33 (CRC-8000series, manufactured by Sumitomo Bakelite Company Limited) isspin-coated for 30 seconds at the speed of 1500 spins per minute by aspin-coating apparatus, and then is baked at 130° C. for five minutes.

In the step of applying an over coat layer, the CRC-8000 series is usedas the over coat layer 33. The material to be used as the over coatlayer 33, however, is not limited to the above material, and for exampleHD-8800 series, manufactured by Hitachi Chemical Co., Ltd., may also beused. Further, a photosensitive heat-resistant resin, such as HK-8000series, may be used as the over coat layer 33.

Further, in the step of apply gin an over coat layer, the spin-coatingapparatus performs the spin-coating for 30 seconds at the speed of 1500spins per minute, and then the semiconductor wafer is baked at 130° C.for five minutes. The method of coating the over coat layer, however, isnot limited to the above arrangement. For example, the semiconductorwafer may be spun at the speed of 1000 spins to 3000 spins per minuteuntil the thickness becomes uniformed, and then may be heated at 120° C.to 140° C. for approximately five minutes.

As illustrated in FIG. 14(c), in the step of forming a pattern on theover coat layer, an arbitrary pattern is formed on the over coat layer33. Specifically, after the step of applying an over coat layer isperformed, the semiconductor wafer having the semiconductor chip 41 isplaced in an exposure device (not illustrated). Then, the exposuredevice illuminates a g-line (436 nm) on the over coat layer 33.Subsequently, a development apparatus (not illustrated) develops theover coat layer 33 using 2.38%-TMAH aqueous solution, a portion of theover coat layer 33, on which portion the external connection terminal 34is to be formed, is removed. Then, after the portion is removed, acuring process is performed for two hours under nitrogen atmosphere at300° C. By the step of forming a pattern on the over coat layer, a partof the wiring plated-layer 16 on the semiconductor chip 41 is exposed,on which part the external connection terminal 34 is to be formed.

In the above case, during the step of forming a pattern on an over coatlayer, the exposure device illuminates a g-line (436 nm) on the overcoat layer 33. The light beam to be illuminated on the over coat layer33, however, is not limited to a particular light beam, as long as thelight beam can expose the over coat layer 33. For example, an i-line(365 nm) or a deep UV (approximately 200 nm to 300 nm) may beilluminated on the over coat layer 33.

Further, in the step of forming the pattern on the over coat layer, theover coat layer 33 is developed using the 2.38%-TMAH aqueous solution.The concentration of the TMAH aqueous solution, however, is not limitedto the above value. For example, the concentration of the TMAH aqueoussolution may be 1% to 3%. Further, 25%-TMAH aqueous solution may bediluted by pure water to a suitable concentration for the development.

Further, in the step of forming a pattern on an over coat layer, a partof the over coat layer 33 is removed, on which part an externalconnection terminal 34 is to be formed, and then the curing process isperformed for two hours under the nitrogen atmosphere at 300° C. Thestep to be performed after the over coat layer is removed, however, isnot limited to the above step. For example, after the over coat layer isremoved, a step of providing a retention period for keeping thesemiconductor wafer at 250° C. to 350° C. for 1.5 hours to 3 hours maybe provided. Further, prior to or subsequent to the step of providing aretention period, a process for increasing the temperature and a processfor reducing the temperature may be provided.

As illustrated in FIG. 14(d), in the step of forming the externalconnection terminal, the external connection terminal 34 is formed onthe part of the over coat layer 33, which part of the over coat layer 33was removed in the step of forming a pattern on an over coat layer.Specifically, the semiconductor wafer having the semiconductor chip 41is placed in a ball mounting apparatus (not illustrated). Then, Flux(not illustrated) is applied on the portion where the wiringplated-layer 16 is exposed for forming the external connection terminaltherein. Then, on the portion where the Flux is applied, a solder ballthat is held by a tool (not illustrated) and functions as the externalconnection terminal 34 is mounted. Subsequently, the semiconductor waferincluding the semiconductor chip 41 on which the solder ball is mountedis processed by a reflow oven with the temperature of 245° C.Specifically, the solder ball is melted again and cooled down so as tobe connected, as the external connection terminal 34, to the wiringplated-layer 16.

In the above case, the solder ball that functions as the externalconnection terminal 34 is made of SnAg3.0Cu0.5 (M705, manufactured bySenju Metal Industry Co., Ltd.). The solder ball, however, is notlimited to the above solder ball, and for example the solder ball may bemade of Sn63Pb37. Alternatively, the solder ball may be made of otherlead-free solder.

Further, in the step of forming an external connection terminal, thereflow oven heats at 245° C. The temperature at which the reflow ovenheats, however, is not limited to the above temperature, and for examplethe temperature may be at 240° C. to 250° C.

As described above, a plating apparatus of the present invention forplating a plating-target face of a plating-target substrate, whichplating apparatus includes a plating tank in which an anode electrode isprovided, performs the plating by (i) streaming a plating solution andan electrolytic liquid into the plating tank, (ii) emitting a jet of theplating solution to the plating-target face of the plating-targetsubstrate from an underneath of the plating-target substrate, and (iii)streaming the electrolytic liquid to the anode electrode provided in theplating tank while electrically conducting between the plating-targetsubstrate and the anode electrode. The plating tank includes a partitionin between the plating-target substrate and the anode electrode, and thepartition (i) separates the plating-target substrate and the anodeelectrode and (ii) divides the plating tank into a plating-targetsubstrate room and an anode electrode room.

This prevents the plating-target face from being contaminated with, forexample, particles originated from the anode electrode, and thereforethe plating quality would not be degraded by micro foreign solidparticles originated from, for example, a black film, while maintainingthe operability of the apparatus.

As described above, the method for manufacturing a semiconductor device,which method accords to the present invention, utilizes the aboveplating apparatus. Further, the method for manufacturing a semiconductordevice, which method accords to the present invention, includes theabove plating method.

Therefore, it becomes possible to provide a semiconductor device havinghigh-quality plating for wiring but no micro foreign solid particlesoriginated from, for example, a black film on the surface of the anodeelectrode.

Further, it is preferable in the plating apparatus of the presentinvention that the electrolytic liquid streaming into the anodeelectrode room does not reach the plating-target substrate room.

The electrolytic liquid streamed into the anode electrode room containsparticles originated from the anode electrode as a result of theelectric conduction between the anode electrode and the plating-targetsubstrate. The particles are removed by passing the electrolytic liquidthrough the partition. Accordingly, with the above structure, theparticles originated from the anode electrode would not reach theplating-target face. Therefore, the plating-target face is preventedfrom being contaminated with the particles.

Further, it is preferable that the plating apparatus according to thepresent invention has an electrolytic liquid outlet opening for drainingthe electrolytic liquid out of the plating tank, the electrolytic liquidhaving streamed into the anode electrode room.

In the above structure, the electrolytic liquid (i) is streaming to theanode electrode in the plating tank and (ii) is draining out of theplating tank through the electrolytic liquid outlet opening, whileelectrically conducting between the anode electrode and theplating-target substrate. Therefore, with the above structure, theparticles originated from the anode electrode can be drained out of theplating tank, and therefore an electrolytic liquid with a reduced numberof particles is constantly supplied to the anode electrode room.

Further, it is preferable in the plating apparatus of the presentinvention that (i) the plating apparatus has a partitioning portionincluding the partition and separating the anode electrode and theplating-target substrate in the plating tank, a part or a whole of thepartitioning portion being made of a permeable member that, when beingsoaked in the electrolytic liquid, is permeable to an ion of theelectrolytic liquid.

In the above structure, the permeable member is permeable to an ion inthe electrolytic liquid when soaked in the electrolytic liquid.Therefore, when a voltage is applied to the electrolytic liquid, theions in the electrolytic liquid transmit through the permeable member,while the particles originated from the anode electrode do not passthrough the permeable member. Thus, with the above structure, the ionsand the particles, both of which are contained in the electrolyticliquid streamed to the anode electrode, can be separated.

Further, the permeable member may be a semipermeable membrane.

Further, the permeable member may contain an ion exchange resin.

Further, it is preferable that the plating apparatus of the presentinvention be provided with plating-target substrate room closing meansfor closing the plating-target substrate.

In the above structure, the plating-target substrate room closing meanscloses the plating-target substrate room. Therefore, the platingsolution streamed into the plating-target substrate room is shut offfrom the atmosphere outside of the plating tank. This (i) prevents theplating tank from being contaminated due to evaporation of the platingsolution during the plating performed in the plating tank, and (ii)prevents a fluctuation in the concentration of the plating solution,which fluctuation may be caused by evaporation of the plating solution.

Further, it is preferable that the plating apparatus of the presentinvention further include: a plating solution supply source that storesplating solution to be supplied to the plating-target substrate room; aplating solution system for circulating the plating solution between theplating solution supply source and the plating-target substrate room; anelectrolytic liquid supply source that stores electrolytic liquid to besupplied to the anode electrode room; and an electrolytic liquid systemfor circulating the electrolytic liquid between the electrolytic liquidsupply source and the anode electrode room.

Further, it is preferable that the plating apparatus of the presentinvention further include a replenishing liquid system in which (i) aconcentration of the plating solution circulating in the platingsolution system, and (ii) replenishing liquid is replenished based uponconcentration information of the plating solution.

The plating solution contains components necessary for metal plating.The “concentration information of plating solution” is concentrationinformation regarding the components that are contained in the platingsolution and are necessary for metal plating. Further, the “replenishingliquid” is a plating solution containing the components at highconcentrations. The components of the plating solution may be sulfuricacid, copper, chlorine, additive agent, and/or the like, for example, inthe case of copper plating.

With the above structure, in the replenishing liquid system, thereplenishing liquid is replenished based upon the concentrationinformation of the plating solution. Specifically, in the replenishingliquid system, the replenishing liquid is replenished when concentrationof a component in the plating solution become lower than a predeterminedmanaged level. Therefore, with the above structure, the plating solutionwith a constant level of concentration can be supplied to the platingtank.

Further, it is preferable in the plating apparatus of the presentinvention that each of the plating solution system and the electrolyticliquid system is a closed system.

This prevents the atmosphere from being contaminated with evaporation ofthe plating solution circulating in the plating solution system orevaporation of the electrolytic liquid circulating in the electrolyticliquid system. Further, a fluctuation in the concentrations of (i) theplating solution and (ii) the electrolytic liquid can be prevented,which fluctuation may be caused due to evaporation of the platingsolution and evaporation of the electrolytic liquid.

Further, it is preferable that the plating solution (i) contain a copperand (ii) be conductive liquid.

There are a variety of plating solutions for forming various metallayers. With the above structure, a plating solution containing copperis used so that the plating-target face of the plating-target substrateis plated with copper. The “copper component” is metallic copper, copperion, or a compound containing copper ion. Further, desirable plating isachieved in the case where the proportion of the copper in 1 L of theplating solution is 14 g to 40 g, inclusive.

Further, it is preferable that the anode electrode be a dissoluble anodeelectrode made of copper mixed with phosphorus.

If an anode electrode made of pure copper is used as the anodeelectrode, then the amount of foreign substances generated from theanode electrode increases. With the above structure, however, becausethe anode electrode is a dissoluble anode electrode made of copper mixedwith phosphorus, a black membrane called black film is formed on thesurface of the anode electrode. This traps copper complex ion (Cu+) thatgenerates the foreign substances. It is preferable that the percentageof the phosphorus to be contained be 0.04% to 0.06%.

Further, conventionally, it is necessary to use an inert electrode inorder to prevent adhesion of the micro foreign solid particlesoriginated from, for example, a black film. This causes problems that(i) the consumption of the additive agent is increased due to oxidativedecomposition of additive agent contained in plating solution and (ii)the plating quality is degraded due to plating solution contaminatedwith decomposition product.

With the present invention, even if a dissoluble anode electrode made ofcopper including phosphorus is used, because the particles originatedfrom the anode electrode are removed by the partition, the micro foreignsolid particles originated from, for example, black film is preventedfrom adhering.

As described above, the “electrolytic liquid” indicates a solutioncontaining no substance that works in relation to the plating-targetface of the plating-target substrate. Specifically, the electrolyticliquid is a solution containing no metal that is the type of metal to beplated in the plating process (for example, copper in the case of copperplating). On the other hand, the plating solution indicates a solutioncontaining the metal to be plated. Both the electrolytic liquid and theplating solution have a conductive property.

Specifically, in the case where a solution containing copper sulfate isused as the plating solution, it is preferable that the electrolyticliquid be (i) sulfuric acid or (ii) an aqueous solution diluted withsulfuric acid.

Further, with the present invention, adhesion of the micro foreignparticles originated from, for example, black film can be prevented evenif the electrolytic liquid is (i) a solution containing metal that isthe type of metal to be plated or (ii) a solution identical to theplating solution. Even if a substance that may cause a negativeinfluence on the plating is generated on the surface of the anodeelectrode, because the plating-target face is separated by thepartition, the plating-target face would not be affected by thesubstance.

Therefore, the electrolytic liquid may be a conductive liquid containinga copper.

Further, the electrolytic liquid may contain a copper at the ratio of 14g to 40 g of copper with respect to 1 L of electrolytic liquid.

Further, in the plating apparatus of the present invention, theplating-target substrate may be a semiconductor wafer. Therefore, itbecomes possible to provide, without spoiling the operability of theface-down type fountain plating apparatus, (i) a semiconductor devicewith which the plating quality would not be degraded by the microforeign solid particles originated from, for example, black film and(ii) a method of producing the semiconductor device. Further, (i)evaporation of the plating solution and the electrolytic liquid can beprevented, and (ii) generation of mist can also be prevented.

Further, it is preferable in the plating method of the present inventionthat the electrolytic liquid streaming into the anode electrode roomdoes not reach the plating-target substrate room.

Further, it is preferable that the plating method of the presentinvention include the step of draining the electrolytic liquid out ofthe plating tank, the electrolytic liquid having streamed into the anodeelectrode room.

Further, it is preferable in the plating method of the present inventionthat the partition that separates the anode electrode and theplating-target substrate includes a permeable member that, when soakedin the electrolytic liquid, is permeable to an ion contained in anelectrolytic liquid.

Further, it is preferable that the plating method of the presentinvention include the step of closing the plating-target substrate room.

Further, it is preferable that the plating method of the presentinvention further include the steps of: circulating the plating solutionplating solution between (i) the plating solution supply source thatstores the plating solution and (ii) the plating-target substrate room;and circulating the electrolytic liquid between (i) the electrolyticliquid supply source that stores the electrolytic liquid and (ii) theanode electrode room.

Further, it is preferable in the plating method of the present inventionthat the step of circulating the plating solution includes the steps of(i) monitoring a concentration of the plating solution and (ii)replenishing a replenishing liquid based upon concentration informationof the plating solution.

Further, in order to solve the above problems, it is preferable that themethod for manufacturing a semiconductor device, which method accords tothe present invention, include the plating method as its plating step.

Further, it is preferable that the method for manufacturing asemiconductor device, which method accords to the present invention,prior to the plating step, further include the steps of: forming a seedlayer on a plating-target face of the plating-target substrate; applyinga photoresist on a surface of the seed layer formed in the step offorming a seed layer; and forming a pattern by exposing and developingthe photoresist.

As the foregoing described, with the plating apparatus of the presentinvention, the plating quality will not be degraded by the micro foreignsolid particles originated from, for example, black film whilemaintaining its operability. Thus, the present invention is applicableto the semiconductor industries.

The present invention is not limited to the description of theembodiments above, but may be altered by a skilled person within thescope of the claims. An embodiment based on a proper combination oftechnical means disclosed in different embodiments is encompassed in thetechnical scope of the present invention.

The embodiments and concrete examples of implementation discussed in theforegoing detailed explanation serve solely to illustrate the technicaldetails of the present invention, which should not be narrowlyinterpreted within the limits of such embodiments and concrete examples,but rather may be applied in many variations within the spirit of thepresent invention, provided such variations do not exceed the scope ofthe patent claims set forth below.

1. A plating apparatus for plating a plating-target face of aplating-target substrate, the plating apparatus comprising: a platingtank in which an anode electrode is provided, the plating apparatusperforming the plating by (i) streaming a plating solution and anelectrolytic liquid into the plating tank, (ii) emitting a jet of theplating solution to the plating-target face of the plating-targetsubstrate from an underneath of the plating-target substrate, and (iii)streaming the electrolytic liquid to the anode electrode provided in theplating tank while electrically conducting between the plating-targetsubstrate and the anode electrode, the plating tank including apartition in between the plating-target substrate and the anodeelectrode, and the partition (i) separating the plating-target substrateand the anode electrode and (ii) dividing the plating tank into aplating-target substrate room and an anode electrode room.
 2. A platingapparatus as set forth in claim 1, further comprising: a platingsolution jet tube for emitting a jet of the plating solution to theplating-target face of the plating-target substrate, the platingsolution jet tube being provided in such a way that (i) the platingsolution jet tube passes through the partition and (ii) the platingsolution streams only into the plating-target substrate room.
 3. Aplating apparatus as set forth in claim 1, further comprising anelectrolytic liquid supply tube for streaming the electrolytic liquidonly into the anode electrode room.
 4. A plating apparatus as set forthin claim 1, wherein the electrolytic liquid streaming into the anodeelectrode room does not reach the plating-target substrate room.
 5. Aplating apparatus as set forth in claim 1, further having anelectrolytic liquid outlet opening for draining the electrolytic liquidout of the plating tank, the electrolytic liquid having streamed intothe anode electrode room,.
 6. A plating apparatus as set forth in claim1, having a partitioning portion including the partition and separatingthe anode electrode and the plating-target substrate in the platingtank, a part or a whole of the partitioning portion being made of apermeable member that, when being soaked in the electrolytic liquid, ispermeable to an ion of the electrolytic liquid.
 7. A plating apparatusas set forth in claim 6, wherein the permeable member is a semipermeablemembrane.
 8. A plating apparatus as set forth in claim 6, wherein thepermeable member contains ion exchange resin.
 9. A plating apparatus asset forth in claim 1, further comprising a plating-target substrate roomclosing means for closing the plating-target substrate room.
 10. Aplating apparatus as set forth in claim 1, further comprising: a platingsolution supply source that stores plating solution to be supplied tothe plating-target substrate room; a plating solution system forcirculating the plating solution between the plating solution supplysource and the plating-target substrate room; an electrolytic liquidsupply source that stores electrolytic liquid to be supplied to theanode electrode room; and an electrolytic liquid system for circulatingthe electrolytic liquid between the electrolytic liquid supply sourceand the anode electrode room.
 11. A plating apparatus as set forth inclaim 10, further comprising a replenishing liquid system for (i)monitoring a concentration of plating solution circulating within theplating solution system and (ii) replenishing a replenishing liquidbased upon concentration information of the plating solution.
 12. Aplating apparatus as set forth in claim 10, wherein each of the platingsolution system and the electrolytic liquid system is a closed system.13. A plating apparatus as set forth in claim 1, wherein the platingsolution is a conductive liquid containing copper.
 14. A platingapparatus as set forth in claim 13, wherein the proportion of the copperin 1 L of the plating solution is 14 g to 40 g, inclusive.
 15. A platingapparatus as set forth in claim 1, wherein the anode electrode is adissoluble anode electrode made of copper mixed with phosphorus.
 16. Aplating apparatus as set forth in claim 1, wherein the electrolyticliquid is (i) sulfuric acid or (ii) an aqueous solution in whichsulfuric acid is diluted.
 17. A plating apparatus as set forth in claim1, wherein the electrolytic liquid is a conductive liquid containingcopper.
 18. A plating apparatus as set forth in claim 17, wherein theproportion of the copper in 1 L of the electrolytic liquid is 14 g to 40g, inclusive.
 19. A plating apparatus as set forth in claim 1, whereinthe plating-target substrate is a semiconductor wafer.
 20. A platingmethod for plating a plating-target face of a plating-target substrate,the plating method comprising the plating steps of: (i) streaming aplating solution and an electrolytic liquid into a plating tank, (ii)emitting a jet of the plating solution to a plating-target face of aplating-target substrate from an underneath of the plating-targetsubstrate, and (iii) streaming the electrolytic liquid to an anodeelectrode provided in the plating tank while electrically conductingbetween the plating-target substrate and the anode electrode; andplating the plating-target substrate in the plating tank in which aplating-target substrate and an anode electrode are separated by apartition so as to divide the plating tank into a plating-targetsubstrate room and an anode electrode room.
 21. A plating method as setforth in claim 20, comprising the plating step performed in such a waythat the electrolytic liquid streamed into the anode electrode room doesnot reach the plating-target substrate room.
 22. A plating method as setforth in claim 20, further comprising the step of draining theelectrolytic liquid out of the plating tank, the electrolytic liquidhaving streamed into the anode electrode room,.
 23. A plating method asset forth in claim 20, wherein: the partition that separates the anodeelectrode and the plating-target substrate, includes a permeable memberthat, when being soaked in the electrolytic liquid, is permeable to anion contained in an electrolytic liquid.
 24. A plating method as setforth in claim 20, further comprising the step of closing theplating-target substrate room.
 25. A plating method as set forth inclaim 20, further comprising the steps of: circulating the platingsolution between (i) the plating solution supply source that stores theplating solution and (ii) the plating-target substrate room; andcirculating the electrolytic liquid between (i) the electrolytic liquidsupply source that stores the electrolytic liquid and (ii) the anodeelectrode room.
 26. A plating method as set forth in claim 25, whereinthe step of circulating the plating solution includes the steps of: (i)monitoring a concentration of the plating solution; and (ii)replenishing a replenishing liquid based upon concentration informationof the plating solution.
 27. A method for manufacturing a semiconductordevice, the method comprising the plating method set forth in claim 20as its plating step.
 28. The method as set forth in claim 27, furthercomprising, prior to the plating step, the steps of: forming a seedlayer on a plating-target face of the plating-target substrate; applyinga photoresist on a surface of the seed layer formed in the step offorming a seed layer; and forming a pattern by exposing and developingthe photoresist.